"Glossary of Geology" "B"

baaken

S. Afr. A boundary mark.




Babcock and Wilcox mill

Dry-grinding mill in which steel balls rotate in a horizontal ring,
through which the feed is worked downward. Pryor, 3




Babel quartz

A variety of quartz, named for the fancied resemblance of the crystal to
the successive tiers of the Tower of Babel. Syn:Babylonian quartz




Babylonian quartz

See:Babel quartz




bacalite

a. A variety of amber. Tomkeieff
b. A variety of quartz in Baja California, Mex.




back

a. A system of joints in coal oblique to the bedding, at an angle of about
35 degrees to 75 degrees . Backs are usually perfectly tight and have
polished cheeks which suggest a certain amount of movement. Back may be
applied to the principal cleat. See also:backs; cleat.
b. The roof or upper part of any underground mining cavity.
c. The ore between a level and the surface, or between two levels.
See also:back of ore
d. That part of a lode which is nearest the surface relative to any
working part of a mine, thus the back of the level or stope is that part
of the unstoped lode which is above. See also:back of lode
e. A joint, usually a strike joint, which is perpendicular to the
direction of working.
f. As applied to an arch, the outer or upper surface.
g. The pavilion of a gemstone.




back acter

Front-end equipment fitted to an excavator, comprising a jib with an arm
and bucket. Although designed primarily for vertically sided trenching, it
is also useful for bulk excavation below track level. Nelson




back and underhand stoping milling system

See:combined overhand and underhand stoping




back arch

A concealed arch carrying the backing or inner part of a wall where the
exterior facing material is carried by a lintel. ACSG, 1




back balance

a. A type of self-acting incline in a mine. A balance car is attached to
one end of a rope, and a carriage for the mine car is attached to the
other end. A loaded car is run on the carriage and is lowered to the foot
of the incline, raising the balance car. The balance car in its descent
raises the carriage when the carriage is loaded only with an empty car.
Fay
b. The means of maintaining tension on a rope transmission or haulage
system, consisting of the tension carriage, attached weight, and
supporting structure. Fay




backblast

See:backlash




back break

Rock broken beyond the limits of the last row of holes marking the outer
boundary in a blast.




back brusher

a. A ripper engaged in taking down the roof in roadways some distance back
from the face. Syn:second ripping
b. Back ripper.




back-bye work

General work performed behind the working faces, as opposed to work done
at the faces. This is commonly referred to as "outby work."




back casing

Eng. A temporary shaft lining of bricks laid dry, and supported at
intervals upon curbs. When the stonehead has been reached, the permanent
masonry lining is built upon it inside of the back casing.




backcast stripping

A stripping method using two draglines, one of which strips and casts the
overburden while the other recasts a portion of the overburden.
Woodruff




back coal

Scot. Coal that miners are allowed to carry home.




back coming

Scot. Working away the pillars that are left when mining coal inby.
Robbing pillars; back working. See also:back work


back-end man

A worker who works behind the coal-cutter as it moves along the face.
Duties may include cleaning the cuttings from behind the machine and
setting props to support the roof or overhang of coal.
CF:coal-cutter team




back entry

The air course parallel to and below an entry or the entry used for
secondary purposes in two-entry system of mining. Locally, any entry not
having track in it. BCI




backfill

a. Waste sand or rock used to support the roof or walls after removal of
ore from a stope. Pryor, 3
b. Sand or dirt placed behind timber, steel, or concrete linings in shafts
or tunnels. Nelson
c. The process of sealing and filling, and/or the material used to seal or
fill, a borehole when completed, to prevent its acting as a course along
which water may seep or flow into rock formations or mine workings.
Long
d. Material excavated from a site and reused for filling, for example, the
use of stones or coarse gravel for filling draining trenches.
See also:fill




back filling

a. Rough masonry built in behind the facing or between two faces; similar
material used in filling over the extrados of an arch; also, brickwork
used to fill in space between studs in a frame building, sometimes called
brick nogging. ACSG, 1
b. The filling in again of a place from which the rock or ore has been
removed. Ballard




back-filling system

Filling lower or older workings with the waste from newer workings.
See also:overhand stoping; square-set stoping. Hess




backfire

a. A fire started to burn against and cut off a spreading fire.
Nichols, 1
b. An explosion in the intake or exhaust passages of an engine.
Nichols, 1




backfolding

Folding in which the folds are overturned toward the interior of an
orogenic belt. In the Alps, the backward folds are overturned toward the
south, whereas most of the folds are overturned toward the north.
Syn:backward folding




background

a. The abundance of an element, or any chemical property of a naturally
occurring material, in an area in which the concentration is not
anomalous. AGI
b. The slight radioactivity shown by a counter, due to normal
radioactivity from cosmic rays, impurities in the counter, and trace
amounts of radioactivity in the vicinity.




backhand

In bituminous coal mining, one who assists either the machineman or
machine loader to move and set up a coal cutting or loading machine at the
working face. DOT




backhaul

A line that pulls a drag scraper bucket backward from the dump point to
the digging. Nichols, 2




backhaul cable

In a cable excavator, the line that pulls the bucket from the dumping
point back to the digging. Nichols, 1




back heading

a. Eng. The companion place to a main winning. SMRB
b. See:back entry




backhoe

The most versatile rig used for trenching. The basic action involves
extending its bucket forward with its teeth-armed lip pointing downward
and then pulling it back toward the source of power. Carson, 1




back holes

In shaft sinking, raising, or drifting, the holes that are shot last.




backing

a. Timbers fixed across the top of a level supported in notches cut in the
rock.
b. The action of a roof layer of combustible gases flowing uphill against
the direction of the ventilation. BS, 8




backing deals

Boards from 1 to 4 in (2.5 to 10 cm) thick and of sufficient length to
bridge the space between timber or steel sets or between rings in skeleton
tubing. Usually, planks 9 to 12 in (23 to 30 cm) in width are used. Round
poles, either whole or split, light steel rails, ribbed sheet metal, and
reinforced concrete slabs are sometimes used in place of planks. Backing
deals tighten the supports against the ground and also prevent the
collapse of material between the timber or steel sets or rings.
See also:lagging




backing off

A term used to describe the operation of removing excessive body metal
from badly worn bits. Fraenkel




backing sand

Reconditioned sand used for supporting the facing sand, and forming the
main part of a foundry mold. Osborne




backjoint

a. A joint plane more or less parallel to the strike of the cleavage, and
frequently vertical. Zern
b. A rabbet or chase left to receive a permanent slab or other filling.
Webster 3rd




backlash

a. The return or counterblast, as the recoil or backward suction of the
air current, produced after a mine explosion. Also called backblast;
suction blast.
b. The reentry of air into a fan.
c. The violent recoil and whipping movement of the free ends of a rope or
wire cable broken under strain. Long
d. Lost motion, play, or movement in moving parts such that the driving
element (as a gear) can be reversed for some angle or distance before
working contact is again made with the secondary element. ASM, 1




back leads

Applied to black sand leads on coastlines which are above high-water mark.
Fay


back mine

Scot. A passage in a mine crosscut toward the dip of the strata.
Standard, 2




back-off shooting

The firing of small explosive charges for releasing stuck drilling tools
in a borehole. The shock of detonation causes the joint to expand and
unscrew slightly. All rods above the joint can then be removed from the
hole. Nelson




back of lode

The portion of a lode lying between a level driven in a lode and the
surface. See also:back




back of ore

The ore between two levels which has to be worked from the lower level.
See also:back




back-out switch

See:hoist back-out switch




back pressure

a. Resistance transferred from rock into drill stem when bit is being fed
at a faster rate than the bit can cut. Long
b. Pressure applied to the underside of the piston in the hydraulic-feed
cylinder to partially support the weight of the drill rods and hence
reduce pressure on the bit. Long
c. Rock pressures affecting the uppermost portion or roof in an
underground mine opening. Long




back prop

The name given to the raking strut that transfers the load from the
timbering of a deep trench to the ground. These struts are provided under
every second or third frame according to the type of ground being
excavated. Hammond




back ripper

See:back brusher




back rippings

The taking down of a thickness of roof beds in roadways some distance back
from the face. The thickness of roof excavated may vary from 1 ft (0.3 m)
or so to 6 ft (1.8 m) and more. This work is necessary where there has
been a gradual reduction in height, as a result of roof sag, and opening
height must be maintained. See also:second ripping




backrush

The seaward return of the water following the uprush of waves. For any
given tide stage, the point of farthest return seaward of the backrush is
known as the limit of backrush or limit of backwash. See also:backwash
AGI




backs

a. The height of ore available above a given working level. If the orebody
has been proved by shaft sinking to a depth of 300 ft (91 m) from the
surface, the orebody is said to have 300 ft (91 m) of backs.
See also:back
b. A quarryman's term for one set of joints traversing the rock, the other
set being known as cutters. Nelson
c. A system of joints in coal or stratified mineral oblique to the bedding
at an angle of 35 degrees to 75 degrees . See also:slips
BS, 11
d. Slips; used to denote a slip met with first at floor level.
Syn:hugger




backs and cutters

Jointed rock structures, the backs (joints) of which run in lines parallel
to the strike of the strata, the cutters (cross joints) crossing them at
about right angles. Standard, 2




backscatter

The emergence of radiation from that surface of a material through which
it entered. Also used to denote the actual backscattered radiation.
NCB




backshift

a. The afternoon or night shift; any shift that does not fill coal or is
not the main coal-production shift. Mason
b. N. of Eng. The second or middle shift of the day; varies from 9 to
10:30 a.m. until 4:30 to 6 p.m. in different pits. Trist




back shot

A shot used for widening an entry; it is placed at some distance from the
head of an entry. Fay




backsight

a. A sight or bearing on a previously established survey point (other than
a closing or check point), taken in a backward direction. AGI
b. A reading taken on a level rod held in its unchanged position on a
survey point of previously determined elevation when the leveling
instrument has been moved to a new position. It is used to determine the
height of the instrument prior to making a foresight. Syn:plus sight
Abbrev: BS. Ant: foresight. AGI




backsight hub

A mark or stake placed at some distance behind the position a drill will
occupy in a specific compass direction from the borehole marker for an
incline hole to enable the driller to set the drill and drill the borehole
in the intended direction. Also called back hub; backsight.
See also:picket




back skin

Newc. A leather covering worn by workers in wet workings.




back slip

A joint in a coal seam that is inclined away from the observer from floor
to roof. It would be a face slip from the opposite direction.
CF:face slip




back slope

a. S. Wales. A slope with the stalls branching off and working the seam
with back slips along the face. Nelson
b. In geology, the less sloping side of a ridge. Contrasted with
escarpment, or steeper slope; esp., the slope more nearly parallel with
the strata. Also called structural plain. Standard, 2
c. The term is used where the angle of dip of the underlying rocks is
somewhat divergent from the angle of the land surface. The slope at the
back of a scarp; e.g., the gentler slope of a cuesta or of a fault block.
It may be unrelated to the dip of the underlying rocks. Also spelled:
backslope. AGI
d. Syn:dip slope




back splinting

The working of the top portion of a thick seam that was left as a roof
when the bottom portion was worked. The top coal is recovered by working
over the goaf or packs of the first working. See also:back work
Nelson


backstamp

The maker's name and/or trademark stamped on the back of pottery flatware
or under the foot of hollowware. Dodd




backstay

A drag or trailer fixed at the back of a haulage train (or set) as a
safety device when going uphill. See also:drag
Mason




backstone

Eng. Shaly mudstone used for cooking slabs, quarried near Delph,
Yorkshire. Also, a bed in the Staffordshire Coal Measures. Arkell




back stope

To mine a stope from working below.




back stopes

Overhead stopes; stopes worked by putting in overhead holes and blasting
down the ore. CTD




backstroke jigging

A process in which strong suction is advocated at all times with the
dense-medium process, since none of the bone medium must be allowed to get
over into the washed coal. Mitchell




backup gear

See:reverse-feed gear




back vent

Scot. An air course alongside the pillar in wide rooms.




backwardation

The situation when the cash or spot price of a metal is greater than its
forward price. A backwardation occurs when a tight nearby situation exists
in a metal. The size of the backwardation is determined by differences
between supply and demand factors on the nearby positions compared with
the same factors on the forward position. There is no official limit to
the backwardation. The backwardation is also referred to as the "back."
Wolff




backward folding

See:backfolding




backwash

a. In uranium leaching, flushing from below of colloidal slime from ion
exchange column after adsorption cycle. The cleaning of sand filters.
b. Water or waves thrown back by an obstruction such as a ship,
breakwater, cliff, etc. AGI
c. The return flow of water seaward on a beach after the advance of a
wave. See also:backrush




back work

a. Any kind of operation in a mine not immediately concerned with
production or transport; literally work behind the face; repairs to roads.
Mason
b. See:back coming; back splinting.




bacon

Eng. Fibrous carbonate of lime, also known as beef and horseflesh; Isle of
Portland. See also:beef




bacon stone

a. Eng. Calcspar colored with iron oxide, Bristol. Arkell
b. An old name for a variety of steatite (rock gypsum), alluding to its
greasy luster. See also:speckstone




baculite

A crystallite that appears as a dark rod. AGI




bad air

Air vitiated by powder fumes, noxious gases, or respirable dust.




baddeleyite

A monoclinic mineral, ZrO2 ; may contain some hafnium, titanium,
iron, and thorium.




badlands

A region nearly devoid of vegetation where erosion has produced, usually
in unconsolidated or poorly cemented clays and silts, a dense and
intricate drainage pattern with short steep slopes and sharp crests and
pinnacles. Specif., the Badlands of the Dakotas.




bad top

A coal mining term indicating a weak roof. Bad top sometimes develops
following a blast. Kentucky




baeumlerite

A colorless chloride of potassium and calcium, KCl.CaCl2 .
Intergrown with halite and tachyhydrite. Orthorhombic.
Syn:chlorocalcite




baff ends

Long wooden edges for adjusting linings in sinking shafts during the
operation of fixing the lining. Zern


baffle board

A board fitted across a compartment in an ore washer to retain the heavy
ore and allow the light material to flow away. Nelson




baffle plate

a. A loading plate attached to the frame of a belt conveyor to prevent
spillage at any loading point. Jones, 1
b. A tray or partition placed in a tower, a heat exchanger, or other
processing equipment to direct or to change the direction of flow of
fluids.
c. A metal plate used to direct the flames and gas of a furnace to
different areas so that all portions of it will be heated; a deflector.




baffler

A partition in a furnace so placed as to aid the convection of heat; a
baffle plate. Fay




baffle tube

A pipe of sufficient length to lower the temperature of hot gases before
the gases enter a furnace. CTD




baffle wall

A refractory wall used to deflect gases or flames from the ware and to
provide better heat distribution in the furnace structure.




bag

a. A paper container roughly 2.5 to 5 cm in diameter and 20 to 46 cm long,
used for placing an inert material, such as sand, clay, etc., into a
borehole for stemming or tamping. Also called a tamping bag.
b. A long tube fastened at the upper end to a pipe leading from a smelter,
and gathered and tied at the lower end. The smoke passes through the
cloth, which catches the solids. The bag is periodically untied and the
dust is shaken out. See also:baghouse
c. A cavity in coal containing gas or water. See also:bag of gas
Tomkeieff
d. Flexible pipe or hose. Also called bagging. Mason
e. S. Staff. A quantity of combustible gases suddenly given off by the
coal seam. See also:bag of foulness
f. York. A miner's term for a variety of inferior coal. Tomkeieff




bag filter

An apparatus for removing dust from dust-laden air, employing cylinders of
closely woven material that permit passage of air but retain solid
particles. Syn:filter




baghouse

Chamber in which exit gases from roasting, smelting, melting, or calcining
are filtered through membranes (bags) that arrest solids such as fine
particulates. See also:bag




bag of foulness

N. of Eng. A cavity in a coal seam filled with combustible gases under a
high pressure, which, when cut into, are given off with much force.
See also:bag




bag of gas

Eng. A gas-filled cavity found in seams of coal. See also:bag




bag powder

Originally applied to black powder loaded in bags, but now applied to a
number of explosives so packed. The bags are long, cylindrical units about
6 in (15 cm) in diameter and weighing 12-1/2 lb (5.67 kg) apiece.
Carson, 1




bag process

A method of recovering flue dust and also sublimed lead, whereby furnace
gases and fumes are passed through bags suspended in a baghouse. The
furnace gases thus are filtered, and the particles in suspension
collected. Fay




bahada

See:bajada




baikalite

A dark-green variety of diopside containing iron; found near Lake Baikal,
Russia.




baikerinite

A thick, tarry hydrocarbon that makes up about one-third of baikerite and
from which it may be separated by alcohol. See also:baikerite




baikerite

a. A waxlike mineral from the vicinity of Lake Baikal, Russia, apparently
about 60% ozocerite. Fay
b. A variety of ozocerite. See also:baikerinite




bail

a. As used by churn drillers, to remove a liquid from a borehole by use of
a tubular container attached to a wire line. See also:bailer
b. The handle on a bucket, cage, or skip by means of which it may be
lifted or lowered. Long
c. A large clevis. Long
d. To dewater a mine with a skip or bailer.
e. As used by the diamond- and rotary-drilling industries, (1) a U-shaped
steel rod with the open ends formed into eyes fitting over two lugs
projecting from the sides of a water swivel, or (2) a U-shaped steel rod
with open ends attached to an open-sided, latch-equipped, circular collar,
that fits around a drill rod and under the base of a water swivel. Both
types of bails are designed to permit circulation of fluid through the
drill rod string while the rods are suspended on the hoist line or while
the rods are being raised or lowered a few feet with the hoisting cable.
Long




bailer

a. A long cylindrical vessel fitted with a bail at the upper end and a
flap or tongue valve at the lower extremity. It is used to remove water,
sand, and mud-laden or cuttings-laden fluids from a borehole. When fitted
with a plunger to which the bailing line is attached, it sucks the liquid
in as it is lifted and is then called a sand pump or an American pump.
Syn:bucket
b. A metal tank, or skip, with a valve in the bottom, used for dewatering
a mine.
c. See:sludger; swab.
d. In bituminous coal mining, a laborer who scoops water from drainage
ditches in a mine with a bucket and empties it into a water car, a ditch
flowing to a natural outlet or to a pumping station. Also called water
bailer. DOT
e. A cylindrical steel container with a valve at the bottom for admission
of fluid, attached to a wire line and used in cable-tool drilling for
recovering and removing water, cuttings, and mud from the bottom of a
well. See also:bail; bailing. AGI




bailiff

Eng. A name formerly used for manager of a mine.




bailing

a. Removal of the cuttings from a well during cable-tool drilling or of
liquid from a well by means of a bailer. Inst. Petrol.
b. Dewatering a mine. See also:bailer
c. Removing rock dust and other material loosened in the drilling by means
of a bucket or ball. Mersereau, 2




bajada

a. A broad, continuous alluvial slope or gently inclined detrital surface
extending from the base of mountain ranges out into and around an inland
basin, formed by the lateral coalescence of a series of alluvial fans, and
having an undulating character due to the convexities of the component
fans; it occurs most commonly in semiarid and desert regions, as in the
Southwestern United States. A bajada is a surface of deposition, as
constrasted with a pediment (a surface of erosion that resembles a bajada
in surface form), and its top often merges with a pediment. Etymol: Sp.,
descent, slope. CF:alluvial slope; alluvial fan. Syn:bahada;
alluvial plain; piedmont plain. AGI
b. See:ladderway
c. Sp. Compound alluvial fans. AGI


baffle board

A board fitted across a compartment in an ore washer to retain the heavy
ore and allow the light material to flow away. Nelson




baffle plate

a. A loading plate attached to the frame of a belt conveyor to prevent
spillage at any loading point. Jones, 1
b. A tray or partition placed in a tower, a heat exchanger, or other
processing equipment to direct or to change the direction of flow of
fluids.
c. A metal plate used to direct the flames and gas of a furnace to
different areas so that all portions of it will be heated; a deflector.




baffler

A partition in a furnace so placed as to aid the convection of heat; a
baffle plate. Fay




baffle tube

A pipe of sufficient length to lower the temperature of hot gases before
the gases enter a furnace. CTD




baffle wall

A refractory wall used to deflect gases or flames from the ware and to
provide better heat distribution in the furnace structure.




bag

a. A paper container roughly 2.5 to 5 cm in diameter and 20 to 46 cm long,
used for placing an inert material, such as sand, clay, etc., into a
borehole for stemming or tamping. Also called a tamping bag.
b. A long tube fastened at the upper end to a pipe leading from a smelter,
and gathered and tied at the lower end. The smoke passes through the
cloth, which catches the solids. The bag is periodically untied and the
dust is shaken out. See also:baghouse
c. A cavity in coal containing gas or water. See also:bag of gas
Tomkeieff
d. Flexible pipe or hose. Also called bagging. Mason
e. S. Staff. A quantity of combustible gases suddenly given off by the
coal seam. See also:bag of foulness
f. York. A miner's term for a variety of inferior coal. Tomkeieff




bag filter

An apparatus for removing dust from dust-laden air, employing cylinders of
closely woven material that permit passage of air but retain solid
particles. Syn:filter




baghouse

Chamber in which exit gases from roasting, smelting, melting, or calcining
are filtered through membranes (bags) that arrest solids such as fine
particulates. See also:bag




bag of foulness

N. of Eng. A cavity in a coal seam filled with combustible gases under a
high pressure, which, when cut into, are given off with much force.
See also:bag




bag of gas

Eng. A gas-filled cavity found in seams of coal. See also:bag




bag powder

Originally applied to black powder loaded in bags, but now applied to a
number of explosives so packed. The bags are long, cylindrical units about
6 in (15 cm) in diameter and weighing 12-1/2 lb (5.67 kg) apiece.
Carson, 1




bag process

A method of recovering flue dust and also sublimed lead, whereby furnace
gases and fumes are passed through bags suspended in a baghouse. The
furnace gases thus are filtered, and the particles in suspension
collected. Fay




bahada

See:bajada




baikalite

A dark-green variety of diopside containing iron; found near Lake Baikal,
Russia.




baikerinite

A thick, tarry hydrocarbon that makes up about one-third of baikerite and
from which it may be separated by alcohol. See also:baikerite




baikerite

a. A waxlike mineral from the vicinity of Lake Baikal, Russia, apparently
about 60% ozocerite. Fay
b. A variety of ozocerite. See also:baikerinite




bail

a. As used by churn drillers, to remove a liquid from a borehole by use of
a tubular container attached to a wire line. See also:bailer
b. The handle on a bucket, cage, or skip by means of which it may be
lifted or lowered. Long
c. A large clevis. Long
d. To dewater a mine with a skip or bailer.
e. As used by the diamond- and rotary-drilling industries, (1) a U-shaped
steel rod with the open ends formed into eyes fitting over two lugs
projecting from the sides of a water swivel, or (2) a U-shaped steel rod
with open ends attached to an open-sided, latch-equipped, circular collar,
that fits around a drill rod and under the base of a water swivel. Both
types of bails are designed to permit circulation of fluid through the
drill rod string while the rods are suspended on the hoist line or while
the rods are being raised or lowered a few feet with the hoisting cable.
Long




bailer

a. A long cylindrical vessel fitted with a bail at the upper end and a
flap or tongue valve at the lower extremity. It is used to remove water,
sand, and mud-laden or cuttings-laden fluids from a borehole. When fitted
with a plunger to which the bailing line is attached, it sucks the liquid
in as it is lifted and is then called a sand pump or an American pump.
Syn:bucket
b. A metal tank, or skip, with a valve in the bottom, used for dewatering
a mine.
c. See:sludger; swab.
d. In bituminous coal mining, a laborer who scoops water from drainage
ditches in a mine with a bucket and empties it into a water car, a ditch
flowing to a natural outlet or to a pumping station. Also called water
bailer. DOT
e. A cylindrical steel container with a valve at the bottom for admission
of fluid, attached to a wire line and used in cable-tool drilling for
recovering and removing water, cuttings, and mud from the bottom of a
well. See also:bail; bailing. AGI




bailiff

Eng. A name formerly used for manager of a mine.




bailing

a. Removal of the cuttings from a well during cable-tool drilling or of
liquid from a well by means of a bailer. Inst. Petrol.
b. Dewatering a mine. See also:bailer
c. Removing rock dust and other material loosened in the drilling by means
of a bucket or ball. Mersereau, 2




bajada

a. A broad, continuous alluvial slope or gently inclined detrital surface
extending from the base of mountain ranges out into and around an inland
basin, formed by the lateral coalescence of a series of alluvial fans, and
having an undulating character due to the convexities of the component
fans; it occurs most commonly in semiarid and desert regions, as in the
Southwestern United States. A bajada is a surface of deposition, as
constrasted with a pediment (a surface of erosion that resembles a bajada
in surface form), and its top often merges with a pediment. Etymol: Sp.,
descent, slope. CF:alluvial slope; alluvial fan. Syn:bahada;
alluvial plain; piedmont plain. AGI
b. See:ladderway
c. Sp. Compound alluvial fans. AGI




baja de metales

Peru. Lowering of ores from mine to mill.




bajo

Colom. Low-lying alluvial mines that have to be unwatered by artificial
means; generally deposits in present riverbeds.




bakerite

A monoclinic mineral, Ca4 B4 (BO4 )(SiO4 )
3 (OH)3 .H2 O ; gadolinite group; in white compact
nodules resembling marble or unglazed porcelain; in the Mohave Desert, CA.




baking

a. A stage in the heating of a clay when the clay particles have lost
plasticity and have formed a moderately hard mass composed of particles
adhering together, the mass remaining porous. See also:vitrifying
Nelson
b. The process of firing shaped clay articles in kilns, in order to give
the clay permanent hardness. CTD
c. Heating to a low temperature in order to remove gases. ASM, 1
d. The hardening of rock material by heat from magmatic intrusions or lava
flows. Prolonged baking leads to contact-metamorphic effects. AGI




bal

A Cornish name for a mine; a cluster of mines.




balance

a. The counterpoise or weight attached by cable to the drum of a winding
engine to balance the weight of the cage and hoisting cable and thus
assist the engine in lifting the load out of the shaft. Fay
b. An instrument for weighing. Fay
c. See:assay balance; balance pit.
d. A beam device specif. designed and calibrated to determine specific
gravity by weighing methods, as in determining the specific gravity of
drilling mud. Long




balance bob

A counterbalance to take the excess weight of the pitwork, or timber
beams, in a shaft; used with the Cornish type of reciprocating pump.
CTD




balance brow

a. A self-acting inclined plane down which the cars of coal are lowered
and the empties elevated upon a carriage or platform. Also called balance
plane; back balance.
b. Eng. An inclined roadway in which a balance is used to assist the
haulage. Also called dilly brow. SMRB




balance car

a. In quarrying, a car loaded with iron or stone and connected by means of
a steel cable with a channeling machine operating on an inclined track.
Its purpose is to counteract the force of gravity and thus enable the
channeling machine to operate with equal ease uphill and downhill.
b. A small weighted truck mounted upon a short inclined track, and
carrying a sheave around which the rope of an endless haulage system
passes as it winds off the drum. Zern




balanced cutter chain

A cutter chain that has the same number of bottom and top picks. It
usually cuts more freely in hard material and is often used for cutting at
higher than floor level. See also:unbalanced cutter chain
Nelson




balanced direct-rope haulage

A modified form of direct-rope haulage, in which a power-driven reversible
pulley (surge pulley) is used instead of a drum. The full trams are hauled
up on one end of the rope while the empties go down on the other end. It
involves a double track or a bypass midway on the haulage plane. The
descent of the empty trams assists in balancing the load being hauled
upwards. Nelson




balanced draft

Applied to combustion units in which forced and induced drafts are
adjusted to give atmospheric pressure in the combustion chamber to avoid
the infiltration of unwanted cold air. Nelson




balanced hoisting

Arrangement of cages or skips in mine shaft in which the winding drum
raises one and at the same time lowers the other, thus reducing power
consumption. See also:balanced winding




balanced ventilation

A system of ventilation in which the districts (each with its separate
split) are so arranged with regard to length and resistance, that the use
of ventilation regulators is unnecessary. Regulators, although sometimes
unavoidable, reduce the efficiency and increase the power required to
ventilate the mine. Nelson




balanced vibrating conveyor

A vibrating conveyor in which the center of gravity of the complete
assembly is held constant by having movement of the trough offset by
opposite movement of some other element.




balanced winding

The conventional method of winding in a mine shaft. As the cage containing
the loaded cars ascends, the other cage containing the empties descends,
and thus the cages and cars are balanced. Balanced winding also implies
the use of a balance rope, and thus, ignoring friction, the only load to
be hoisted is the coal or mineral. See also:winding; balanced hoisting.
Nelson




balance pit

Eng. A pit or shaft in which a balance (counterweight) rises and falls.
See also:balance




balance plane

See:balance brow




balance rope

A steel-wire rope, generally of the same weight per foot as the main
winding rope, that is attached to the bottom of the cages, and extends
down to form a loop in the shaft bottom or sump. Its function is to
balance out the difference in weight of the upgoing or downgoing main
ropes during the wind. See also:winding




balance sheet

A record showing the present financial obligations and resources of the
company, in terms of cost or book value. Hoover




balance shot

In coal mining, a shot for which the drill hole is parallel to the face of
the coal that is to be broken by it.


balas

See:balas ruby




balas ruby

A pale rose-red or orange variety of spinel in Badakhshan (Balascia)
Province of northern Afghanistan. Syn:balas; ballas; false ruby.




balata belt

A belt with normal multi-ply construction, and in which balata is used to
impregnate the plies and provide cover. It cannot be used in high
temperatures but possesses a very high resistance to water absorption and
is thus well suited for wet conditions. Nelson




Balbach process

Electrolytic separation of gold from silver, using the alloy as anode,
graphite plate cathodes, and silver nitrate solution as bath.
Bennett




bald

Without framing; said of a mine timber that has a flat end.




bald-headed anticline

An anticline whose crest has been eroded prior to deposition of an
unconformably overlying sedimentary unit. CF:breached anticline
AGI




balistite

See:ballistite




balkstone

a. Eng. A provincial name given to an impure stratified limestone.
Fay
b. Sandstone used for whetstone. Also called balkerstone. Arkell




ball

a. A rounded mass of spongy iron, prepared in a puddling furnace; a loup.
Fay
b. A mass of tempered fire clay, used for forming the crucible in
crucible-steel production. See also:ballstone




ball-and-socket reamer

A borehole-reaming device consisting of a bit attached to a
ball-and-socket or a knuckle-joint member, that in turn is connected to
the drill rods and used in borehole-deviation drilling. Also called arc
cutter. Long




ball and test

A deep well pump valve in which a ball fits into a seat and prevents the
backflow of oil or water. Each standing valve and each traveling valve has
a ball and seat. Hess




ballas

a. A hard, spherical aggregate of many very small diamond crystals,
usually cryptocrystalline, arranged radially and more or less
concentrically around a central point. Because of their structure, ballas
are classed as industrials that are occasionally used in diamond-drill
bits and other diamond tools. See also:shot bort
b. A dense, globular aggregate of minute diamond crystals, having a
confused radial or granular structure lacking through-going cleavage
planes, giving it a toughness that makes it useful as an "industrial
diamond". CF:bort; carbonado.
c. A term incorrectly applied to a rounded, single crystal of diamond.
d. See:balas ruby




ballast

a. Broken stone, gravel, water, or other heavy material used to provide
weight in a ship or other machine and therefore improve its stability or
control its draft. Jettisoned ballast may be found in samples of marine
sediments. AGI
b. Gravel, broken stone, expanded slag, or similar material used as a
foundation for roads, esp. that laid in the roadbed of a railroad to
provide a firm bed for the ties, distribute the load, and hold the track
in line, as well as to facilitate drainage. AGI




ballast car

A freight car (as for carrying ballast) that may be unloaded from the side
or bottom. Webster 3rd




ballast engine

A steam engine used in excavating and for digging and raising stones and
gravel for ballast. Webster 3rd




ballast shovel

A spoon-pointed iron shovel having a thick body. Standard, 2




ball bearing

A friction-reducing device consisting of hard steel balls in a circular
race; also applied to some pieces of equipment, such as a swivel-type
double-tube core barrel, in diamond drilling using ball bearings as
load-bearing members on rotating parts. See also:bearing




ball burnishing

a. See also:ball sizing
b. Removing burrs and polishing small stampings and small machined parts
by tumbling. ASM, 1




ball clay

A highly plastic, sometimes refractory clay, commonly characterized by the
presence of organic matter, having unfired colors ranging from light buff
to various shades of gray, and used as a bonding constituent of ceramic
wares; pipe clay. It has high wet and dry strength, long vitrification
range, and high firing shrinkage. Ball clay is so named because of the
early English practice of rolling the clay into balls weighing 30 to 50 lb
(13 to 22 kg) and having diameters of about 10 in (25 cm). AGI




ballers

White sand with large spheroidal masses of calciferous sandstone called
sand ballers or giants' marbles, some being 3 to 6 ft (approx. 1 to 2 m)
in diameter. (Possibly a variant of "bollars," a dialect form of
boulders.)




ball grinder

A pulverizer or disintegrator consisting of metal balls enclosed in a
rotating cylinder. Fay


ball head

See:ball stamp




balling

a. A process that occurs in the cementite constituent of steels on
prolonged annealing at 650 to 700 degrees C. CTD
b. The operation of forming balls in a puddling furnace.
Syn:nodulizing




balling formation

Rock or formations that, when drilled, produce cuttings and sludge that
tend to collect on, and adhere to, borehole walls and drill-stem equipment
in sticky or gummy masses. CF:gummy; sticky. Long




balling furnace

a. A kind of reverberatory furnace used in alkali works. Fay
b. A furnace in which piles or fagots of wrought iron are placed to be
heated preparatory to rolling. Fay




balling tool

A tool used in collecting the iron in a puddling furnace into a mass,
preparatory to taking it to the hammer or squeezer; a rabble. Fay




ball ironstone

a. A sedimentary rock containing large argillaceous nodules of ironstone.
AGI
b. Nodular iron ore.




ballistic mortar test

A laboratory instrument used for measuring the relative weight strength of
an explosive material. Also, a test in which a standard weight of
explosive is placed within a small borehole fitted with a projectile. The
mortar, suspended on a pendulum, recoils upon detonation. The recoil is a
measure of the weight strength in percentage (relative to a standard whose
value is 100) or pendulum deflection. Meyer




ballistite

A smokeless powder consisting essentially of soluble cellulose nitrates
and nitroglycerin in approx. equal parts. Syn:balistite
Webster 3rd




ball jasper

a. Jasper showing concentric red and yellow bands.
b. Jasper occurring in spherical masses.




ball mill

A rotating horizontal cylinder with a diameter almost equal to the length,
supported by a frame or shaft, in which nonmetallic materials are ground
using various types of grinding media such as quartz pebbles, porcelain
balls, etc. Syn:air-swept ball mill; cannonball mill; jar mill.




ball mill grindability test

Crushed particles of a given size range are placed in a ball mill; the
reduction in size of particles for a given number of revolutions of the
mill is interpreted in terms of a grindability index. Lewis




ball milling

A method of grinding and mixing material, with or without liquid, in a
rotating cylinder or conical mill partially filled with grinding media
such as balls or pebbles. ASTM




ball mill method

A grindability method based on the principle that all coals are ground to
the same fineness, about that required for pulverized fuels, and then
using the relative amounts of energy required for this reduction in size
as a measure of grindability. Mitchell




Ball-Norton magnetic separator

Dry separator for coarse ore, in which one or two nonmagnetic drums rotate
outside a series of fixed magnets alternating in polarity.
Pryor, 3




balls

a. Common name for nodules, esp. of ironstone. Arkell
b. In fine grinding, crushing bodies used in a ball mill. Cast or forged
iron or steel, or alloy of iron with molybdenum or nickel, are used,
mainly spherical; various other shapes are favored locally, e.g., concave.




ball sizing

Sizing and finishing a hole by forcing a ball of suitable size, finish,
and hardness through the hole or by using a burnishing bar or broach
consisting of a series of spherical bands of gradually increasing size
coaxially arranged. Also called ball burnishing, and sometimes ball
broaching. ASM, 1




ball stamp

A rock-crushing stamp whose stem is the piston rod of a steam cylinder.
Syn:ball head




ballstone

a. An ancient term for ironstone, North Staffordshire, U.K.
b. A large crystalline mass of limestone containing coral in position of
growth, surrounded by shale and impure bedded limestone.
See also:caballa ball
c. A nodule or large rounded lump of rock in a stratified unit; specif. an
ironstone nodule in a coal measure. Syn:ball




ball vein

A stratum in which siderite concretions occur; also, the ore itself.
Hess




bally seating

Underclay with nodular concretions. Arkell




balmaiden

Corn. A woman employed in the mines. Standard, 2


balnstone

Eng. Stone in the roof of a coal seam; roof stone. Arkell




baltimorite

A grayish-green and silky, fibrous, or splintery variety of serpentine;
near Baltimore, MD. See also:antigorite




banakite

A basaltic rock composed of olivine and clinopyroxene phenocrysts in a
groundmass of labradorite with alkali feldspar rims, olivine,
clinopyroxene, some leucite, and possibly quartz. Banakite grades into
shoshonite with an increase in olivine and clinopyroxene and with less
alkali feldspar, and into absarokite with more olivine and clinopyroxene.
It was named by Iddings in 1895 from the Bannock (or Robber) Indians.
AGI




banalsite

An orthorhombic mineral, BaNa2 Al4 Si4 O16 ;
feldspar group.




band

a. Shale or other rock interstratified with coal, e.g., dirt band, sulfur
band, etc.
b. A thin stratum or lamina of conspicuous lithology or color. A group of
such layers is described as being banded. CF:parting
c. Any well-defined and widespread thin rock deposit that is of value in
correlation.
d. Slate or other rock interstratified with coal, commonly called middle
band in Arkansas; also, dirt band, sulfur band, or other band, as the case
may be. Fay
e. Applied to a stratum or lamina conspicuous because it differs in color
from adjacent layers; a group of layers displaying color differences is
described as being banded. AGI




band chain

A steel or invar tape of a minimum length of 100 ft (30.5 m) used for
accurate surveying, graduated in feet. See also:reglette
Hammond




band conveyor

See:belt conveyor




banded

The property of rocks having thin and nearly parallel bands of different
textures, colors, or minerals. Banded coal has alternating bands of
different types. Johannsen; Pryor, 3




banded agate

Agate in colors disposed in parallel or subparallel bands, more or less
wavy or sinuous. Most agate in the trade is dyed, and bands are of
differing tones due to varying capacity to absorb the dye.
See also:agate; onyx.




banded coal

a. The common variety of bituminous and subbituminous coal. It consists of
a sequence of irregularly alternating layers or lenses of homogeneous
black material having a brilliant vitreous luster; grayish-black, less
brilliant, striated material usually of silky luster; and generally
thinner bands or lenses of soft, powdery, and fibrous particles of mineral
charcoal. The difference in luster of the bands is greater in bituminous
than in subbituminous coal. Also called bright-banded coal; common-banded
coal.
b. Coal composed of roughly parallel, dull and bright layers.
BS, 4




banded differentiate

Any igneous rock made up of bands of differing chemical or mineral
composition, usually an alternation of two rock types; a layered
intrusion. The structure has been attributed to rhythmic crystal settling
during convection.




banded ingredient

One of the four distinctive and visibly differing portions forming the
mass of an ordinary bituminous coal that can be recognized and separated
macroscopically by hand, and microscopically in thin sections, and that
are not, in themselves, chemical entities; i.e., vitrain, clarain, fusain,
and durain. See also:rock type




banded iron formation

Iron formation that shows marked banding, generally of iron-rich minerals
and chert or fine-grained quartz. Abbrev: BIF. AGI




banded ironstone

A term used in South Africa for iron formation consisting essentially of
iron oxides and chert occurring in prominent layers or bands of brown or
red and black. This usage of the term ironstone is at variance with that
applied in the United States and elsewhere. Syn:ironstone




banded obsidian

Obsidian with differently colored irregular bands.




banded ore

Ore composed of bands as layers that may be composed of the same minerals
differing in color, textures, or proportions, or they may be composed of
different minerals. Syn:banded texture




banded peat

Peat composed of bands of vegetable debris alternating with bands of
sapropelic matter. Tomkeieff




banded-quartz hematite

See:itabirite




banded quartz-hematite ore

Braz. In the Itabira Region of Minas Gerais, schistose, specular hematite
forming alternate bands with sugary quartz. Some of the beds are
auriferous and contain gold-palladium alloys with manganese oxides, native
copper, and talc. Writers have given the rocks various names, such as
iron-glance schist, jacutinga, quartz itabirite, and bandererz.
Hess




banded structure

a. An outcrop feature developed in igneous and metamorphic rocks as a
result of alternation of layers, stripes, flat lenses, or streaks
differing conspicuously in mineral composition and/or texture. AGI
b. A term applied to veins having distinct layers or bands. This may be
due to successive periods of deposition or replacement of some earlier
rock. Fay
c. A structure developed in many igneous and metamorphic rocks owing to
layers that differ noticeably in mineral composition or texture.
d. A segregated structure of nearly parallel bands aligned in the
direction of working. ASM, 1




banded texture

See:banded ore


banded vein

A vein made up of layers of different minerals parallel with the walls.
Also called ribbon vein. Fay




band scale

An arrangement by which colliers are paid an agreed sum for removing a
dirt band, in addition to the usual tonnage rate. The payment varies with
the thickness of the band. Nelson




band wander

In concentration on shaking table, the movement of a segregated band of
mineral so that it no longer discharges from the table deck at the desired
point and therefore is not correctly collected. See also:wander
Pryor, 1




bandylite

A tetragonal mineral, CuB(OH)4 Cl ; occurs as dark blue crystals in
Chile.




bandy metal

Shale with thin sandstone bands. Arkell




bank

a. A large pile of mineral material on the ground surface, as in heap
leaching.
b. Several like pieces of equipment set close together, as a bank of
flotation cells, hydrocyclones, or generators.
c. The surface around the mouth of a shaft. Zern
d. The whole or sometimes only one side or one end of a working place
underground.
e. A hill or brow.
f. A road along the coal face formed by the coal on one side and the waste
or packs on the other; thus, a double-unit face has a right and left bank.
g. A generally steeply sloping mass of any earthy or rock material rising
above the digging level from which the soil or rock is to be extracted
from its natural or blasted position in an open-pit mine or quarry.
Syn:bench face
h. Terracelike bench from which ore is obtained in an open-pit mine.




Banka drill

A portable, manually operated system used in prospecting alluvial deposits
to depths of 50 ft (15.2 m) or more. Also known as an Empire drill.




bank claim

A mining claim on the bank of a stream.




bank coal

Coal contained in, and sometimes salvaged from, the bank. BCI




bank engine

Eng. An engine at the mouth of a mine shaft. Standard, 2




banker off

Aust. The worker who attends to taking skips off the cage. Fay




banket

a. A general term for a compact, siliceous conglomerate of vein-quartz
pebbles about the size of a pigeon's egg, embedded in a quartzitic matrix.
The term was originally applied in the Witwatersrand area of South Africa
to the mildly metamorphosed gold-bearing conglomerates containing
muffin-shaped quartz pebbles and resembling an almond cake made by the
Boers. Etymol: Afrikaans, a kind of confectionery. AGI
b. Originally applied by the Dutch settlers to the gold-bearing
conglomerates of the Witwatersrand. It is now used more widely for similar
conglomerates and conglomeratic quartzites. CTD




bank gravel

Gravel found in natural deposits, usually more or less intermixed with
sand, silt, or clay. AGI




bank head

a. The upper end of an inclined plane, next to the engine or drum, made
nearly level. Zern
b. The mouth and immediate environs of a coal mine. Webster 3rd




bank height

The vertical height of a bank as measured between its highest point or
crest and its toe at the digging level or bench. CF:berm
bench height; digging height.




banking

a. The bringing of a cage to a stop at the rail level (the pit top or
bank) and the replacement of loaded mine cars by empty ones and the
release of the cage for its return journey.
b. Closing down a blast furnace which is still full of burden.




bank measure

a. The quantity of an excavation measured in place in the bank before
being disturbed. Carson, 1
b. Volume of soil or rock in its original place in the ground.
Nichols, 2




bank mining

Surface mining in which the material mined is removed from above the
surrounding land surface. AIME, 2




bank of cells

A row of flotation cells in line. Pryor, 4




bank of ovens

A row of ovens for converting coal into coke. Fay




bank protection

Devices for minimizing scour. These include brushwood held in place by
wooden pegs, embankments, grass and withy planting, groins, mattresses,
revetments, and riprap. Hammond


bank pump

An auxiliary pump placed on the bank of a stream or a lake and used to
pump water to a distant drill. Also called supply pump. Long




bank right

The right to divert water for working a bank claim. Pryor, 3




bank slope

The angle, measured in degrees of deviation from the horizontal, at which
the earthy or rock material will stand in an excavated, terracelike cut in
an open-pit mine or quarry. Syn:bench slope




bank slope stability

A slope is subject to the influence of gravity and possible pressure of
ground water, which tend to cause sliding or caving. It is also subject to
surface erosion from running water, wind, and alternate freezing and
thawing, or wetting and drying. Weathering causes changes in particle size
and composition. Bank slope stability can be attained by benching, by
growth of vegetation, and by artificial protections, such as masonry
walls, drainage systems to intercept or remove ground water, and fences to
catch rolling pieces. See also:stability




banksman

The person in charge of the shaft and cage or skip at the surface of a
colliery; the person at the surface who operates the signals from the cage
or skip to the winding engineman. See also:cager




bank water

In placer mining, applied to streams brought to the pit in ditches, not
under pressure. Hess




bankwork

Eng. A system of working coal in South Yorkshire.




bank yards

Yards of soil or rock measured in its original position, before digging.
Nichols, 2




banos

Mex. Water collected in old mine workings.




banqueria

Bol. In alluvial mining, a thick bed of blocks of granite, schists, and
quartz.




bantams

Small pebbles of a banded garnet-quartz rock; usually associated with
diamond in the concentrate obtained when washing the diamond-bearing
gravels from the Vaal River in the Republic of South Africa. The
occurrence of bantams in a gravel deposit is considered a good indicator
of diamond. Chandler




baotite

A tetragonal mineral, Ba4 (Ti,Nb)8 Si4 O28 Cl.




bar

a. A placer deposit, generally submerged, in the slack portion of a
stream. Also, an accumulation of gravel along the banks of a stream; bar
diggings.
b. A mass of inferior rock in a workable deposit of granite. AGI
c. A fault across a coal seam or orebody. AGI
d. A banded ferruginous rock; specif. jaspilite. AGI
e. A vein or dike crossing a lode.
f. Any band of hard rock crossing a lode. Arkell
g. A unit of pressure equal to 1,000,000 dyn/cm2 , 1,000 mb (100
kPa), or 29.53 in (750 mm) of mercury. Hunt
h. A bank of sand, gravel, or other matter, esp. at the mouth of a river
or harbor, often obstructing navigation. Webster 2nd
i. An offshore ridge or mound of sand, gravel, or other unconsolidated
material submerged at least at high tide, esp. at the mouth of a river or
estuary, or lying a short distance from, and usually parallel to, the
beach. Hunt
j. A drilling or tamping rod. Fay
k. A strap or beam used to support the roof between two props or other
supports. Mason
l. A length of steel pipe equipped with a flat cap at one end and a
jackscrew on the opposite end by means of which the pipe may be wedged
securely in a vertical or horizontal position across an underground
workplace to serve as a base on which a small diamond or rock drill may be
mounted. Syn:drifter bar; drill bar; drill column. Long
m. A heavy steel rod with either pointed or flattened ends used as a pry
or as a tool by miners to dislodge loose rock in roof or sidewalls of an
underground workplace. Syn:scaling bar
n. A piece of material thicker than sheet, long in proportion to its width
or thickness, and whose width-thickness ratio is much smaller than that of
sheet or plate, as low as unity for squares and rounds. ASM, 1




baralyme

A compressed pill consisting of a blended mixture of barium octohydrate
and calcium hydroxide. It is used as a carbon dioxide absorbent in
rebreathing (diving) systems. Hunt




bararite

A hexagonal mineral, (NH4 )2 SiF6 ; dimorphous with
cryptohalite; occurs over a burning coal seam.




bar-belt conveyor

A conveyor similar to a plate-belt conveyor but in which spaced steel rods
arranged transversely are employed in place of the steel plates.
BS, 5




barbertonite

A hexagonal mineral, Mg6 Cr2 (CO3 )(OH)16 .4H
2 O ; manasseite group; rose-pink to violet; dimorphous with
stichtite.




barbosalite

A hydrous ferrous ferric phosphate, Fe2+ Fe3+2
(PO4 )2 (OH)2 ; occurs as black grains from Brazil.
Syn:ferro-ferri-lazulite




bar channeler

A reciprocating drill mounted on a bar by means of which holes are drilled
close together in line by shifting the drill from point to point along the
bar. Thereafter, the webs between the holes are removed with a
reciprocating chisel-pointed broaching tool that is substituted for the
drill. This method of channeling is generally employed in the harder
rocks, such as granites. Hess




bar coal cutter

A coal cutter in which the cutting member was a projecting rotating bar
armed with picks throughout its length. The bar cut a kerf in the seam as
the machine traveled along the face. The first patent for a bar machine
was taken out in 1856. The cutter is now obsolete. Nelson




bar diggings

A term applied in the Western United States to diggings for gold or other
precious minerals located on a bar or in the shallows of a stream, and
worked when the water is low. See also:bar mining


bar drill

A small diamond- or other-type rock drill mounted on a bar and used in an
underground workplace. Also called bar and used in an underground workbar
rig. Long




bare

a. To cut coal by hand; to hole by hand. Mason
b. The uncased portion of borehole. Also called called barefoot; blank;
naked; open; open hole. See also:blank hole
c. To remove overburden. Arkell
d. Eng. To strip or cut by the side of a fault, boundary, etc.; to make
bare.




barefoot

Said of an oil well without a liner in the oil-bearing rock.
See also:blank hole




bare motor

A motor without a pulley, belt-tightening base, or slide rails.
NEMA, 2




barequear

Colom. In placer mining, to extract as much of the pay gravel as possible,
without method, leaving the overburden untouched.




barequeo

Colom. Extracting the rich ore by crude means.




barequero

Colom. A placer miner who uses crude methods of alluvial washing. A
spoiler.




barer

A worker who removes surface soil or overburdens in a quarry.
Arkell




barfe Saturday

N. of Eng. The Saturday on which wages are not paid.




bar flight conveyor

See:drag-chain conveyor; flight conveyor.




barge loader

In the quarry industry, a laborer who controls the movement of a barge in
a river as it is loaded with crushed rock. DOT




barges

Scot. Sheets of iron, zinc, or wood, used in wet shafts or workings for
diverting the water to one side.




bar grizzly

A series of spaced bars, rails, pipes, or other members used for rough
sizing of bulk material passed across it to allow smaller pieces to drop
through the spaces. See also:grizzly




barilla

An impure sodium carbonate and sulfate obtained by burning various species
of land or marine plants; soda ash. See also:copper barilla; coro-coro.
Standard, 2




baring

a. The small coal made in undercutting coal seams. Webster 3rd
b. A making bare; an uncovering. See also:strip
c. The surface soil and useless strata overlying a seam of coal, clay,
ironstone, etc., that have to be removed preparatory to working the
mineral. See:overburden




barite

a. An orthorhombic mineral, 4[BaSO4 ] ; has nearly pseudocubic
cleavage; occurs as interpenetrant masses of crystals with sand and clay
(desert roses); sp gr, 4.5; in veins or in residual masses on limestone;
the principal source of barium. Syn:barytes; dreelite; heavy spar;
cawk.
b. The mineral group anglesite, barite, and celestine.




barite rosette

See:petrified rose




barium

A silvery-white, metallic element, belonging to the alkaline earth group.
Symbol, Ba. Found chiefly in barite or heavy spar and witherite. All
barium compounds that are water or acid soluble are poisonous. Used in
paint, X-ray diagnostic work, glassmaking, oilwell drilling fluids, and
pyrotechny. Handbook of Chemistry and Physics, 3




barium feldspar

See:paracelsian




Barkhausen effect

Observed result of magnetizing a ferromagnetic substance by means of a
slow magnetic field increase. Orientation of domains proceeds in abrupt
steps. Pryor, 3




barley

A stream size of anthracite known also as buckwheat No. 3, sized on a
round punched plate. It passes through 1/4-in (6.4-mm) holes. At some
mines, it has to pass over 3/32-in (2.4-mm) holes and at others over
1/16-in (1.6-mm) holes. The American Society of Mechanical Engineers has
recommended that with a screen with circular holes, barley shall pass
through 3/16-in (4.8-mm) holes and pass over 3/32-in holes.
See also:anthracite coal sizes; bird's-eye. Fay


bar mining

The mining of river bars, usually between low and high waters, although
the stream is sometimes deflected and the bar worked below water level.
See also:bar diggings




barnesite

a. A monoclinic mineral, (Na,Ca)2 V6 O16 .3H2
O .
b. Trademark for a rare-earth oxide used in glass polishing.




barograph

A barometer that makes a continuous record of changes in atmospheric
pressure. It is usually an aneroid type. See also:barometer
AGI




barometer

An instrument that is used to measure atmospheric pressure. It may be
either a mercury barometer or an aneroid barometer. See also:barograph
AGI




barometric leg

In filtering system, use of a loop more than 30 ft (9.1 m) high between
receiving vessel and vacuum pump, to protect latter against carryover of
liquid. Pryor, 3




barometric leveling

A type of indirect leveling in which differences of elevation are
determined from differences of atmospheric pressure observed with
altimeters or barometers. AGI




barometric pressure

The barometric pressure of the air at any point is that exerted by the
weight of the atmosphere above that point. It therefore varies with the
elevation of the point above or the depth below sea level. Barometric
pressure is measured by the mercury barometer, and is of the order of 30
in (762 mm) of mercury at sea level. Spalding




baroque

a. Any pearl of very irregular form.
b. A baroque pearl; said of a pearl, or of a tumble-polished gem material,
of irregular shape.




barotrauma

A generic term for injury caused by pressure. Although squeeze is a
colloquialism, it is an excellent descriptive term for all of the
phenomena that occur when a rigid closed space within the body or on its
surface fails to equalize with external pressure during descent, or is for
some reason vented to lower pressure than that acting at the depth.
Hunt




barranca

A precipice; as used in some parts of Spanish America, a ravine or small
canyon. Also spelled barranco.




barrandite

A mineral intermediate between strengite and variscite.




barrel

a. As used in the petroleum industry, a volumetric unit of measurement
equivalent to 42 U.S. gal (159.0 L). AGI
b. The cylindrical part of a pump from which the movement of the piston
causes a liquid or gas to be forcibly ejected. Also, the cylindrical part
of a hydraulic jack or of a hydraulic-feed mechanism on a diamond drill.
Long
c. The drum of a hoist. Long
d. A cylindrical container or drum having a capacity of 55 gal (208.2 L).
Long
e. The water passage in a culvert. Nichols, 1
f. Commonly, although incorrectly, used as a syn. for core barrel.
See also:drum




barrel copper

Pieces of native copper occurring in sizes large enough to be extracted
from the gangue, and of sufficient purity to be smelted without mechanical
concentration. Syn:barrel work




barrel of oil

A volumetric unit of measurement equivalent to 42 U.S. gal (159.0 L).
AGI




barrel washer

A washer comprising a cylinder rotating slowly about an axis that is
slightly inclined to the horizontal, and into which the raw coal, with a
current of water or of a suspension, is fed near its upper end. The clean
coal is carried by the water or suspension to the lower end of the
cylinder over a scroll that conveys the reject to the upper end of the
cylinder. BS, 5




barrel work

Syn:barrel copper




barren

a. In leaching ores, said of a chemical solution from which valuable
solute has been removed by precipitation, ion exchange, or solvent
extraction before reuse. Pryor, 1
b. Said of rock or vein material containing no minerals of value, or of
strata without coal, or containing coal in seams too thin to be workable.




barren ground

Strata containing seams of coal that are not of a workable thickness. In
metal mining, ground that does not contain ore.
See also:dead bed




barren hole

See:blank hole




barren measures

Coal measures without workable seams. Standard, 2
o?*?üP DICTIONARY TERMS:barren mine A mine may be fully developed and yet,
[\B]barren mine[\N]




barren solution

A solution in hydrometallurgical treatment from which all possible
valuable constituents have been removed; it is usually recycled back to
plant for reuse in process. See also:cyanide


barricade

a. The process of building a set of barriers to isolate a sufficient
quantity of good air to protect mine workers from the asphyxiating gases
formed after a fire or explosion. Miners wait behind the barrier until
rescued. Used as an alternative to an escape attempt.
b. An artificial mound of earth, usually as high as the eaves of a
magazine roof, that is erected to deflect the force of an explosion upward
and to protect the enclosed building from flying objects.
c. Timber formwork to contain the material during hydraulic flushing in
steep ore workings. Nelson




barrier

Blocks of coal left between the workings of different mine owners and
within those of a particular mine for safety and the reduction of
operational costs. It helps to prevent disasters of inundation by water,
of explosions, or fire involving an adjacent mine or another part of a
mine and to prevent water running from one mine to another or from one
section to another of the same mine. See also:barrier pillar
Mason




barrier gate

Eng. See:tailgate




barrier materials

Materials such as lead and concrete that are used for protection from
X-rays or gamma rays in radiographic installations. Osborne




barrier pillar

a. A solid block or rib of coal, etc., left unworked between two
collieries or mines for security against accidents arising from an influx
of water. See also:barrier; pillar; barrier pillar. Zern
b. Any large pillar entirely or relatively unbroken by roadways or airways
that is left around a property to protect it against water and squeezes
from adjacent property, or to protect the latter property in a similar
manner. Zern
c. Incorrectly used for a similar pillar left to protect a roadway or
airway, or group of roadways or airways, or a panel of rooms from a
squeeze. Zern




barrier system

N. of Eng. An approved method of working a colliery by pillar and stall,
where solid ribs or barriers of coal are left in between working places.
Fay




bar rig

A small diamond or other rock drill designed to be mounted and used on a
bar. Also called bar drill. Long




barring

The end and side timber bars used for supporting a rectangular shaft. The
bars are notched into one another to form a rectangular set of timber.
Common sizes are from 9 to 12 in (23 to 30.5 cm) deep and from 3 to 6 in
(7.6 to 15.2 cm) thick and may be made from larch, white pine, or red
pine. See also:cribbing; steel rectangular shaft supports.
Nelson




barring down

a. Loosening ore in a bin by means of a bar, so it will flow through the
chute.
b. Prying off loose rock after blasting to prevent danger of fall.
Pryor, 1




barrings

A general term for the setting of bars of timber for supporting
underground roadways or shafts. Nelson




barring scrap

Prying adhering scrap metal from runners, ladles, or skimmers. Fay




barro

A Spanish and South American term for clay, loam, marl, or the overburden
of alluvial gold deposits.




barroisite

A dark green amphibole intermediate between hornblende and glaucophane.
English




barrow

a. A wicker basket in which salt is put to drain. Webster 2nd
b. A box with two handles at one end and a wheel at the other.
Zern
c. A vehicle in which ore, coal, etc., is wheeled; a push cart.




barrowman

In mining, one who pushes shallow-bodied cars (barrows) or wheelbarrows
used for transporting coal or ore along underground haulageways that are
too low for ordinary mine cars. Also called buggyman. DOT




barrowway

a. A level through which coal or ore is wheeled.
b. Rails laid between the flat or siding and the coal face. SMRB




Barry mining

See:Nottingham system




barsanovite

See:eudialyte




bar screen

See:grizzly




bar timbering

A method of timbering mine roadways by means of horizontal and upright
bars. See also:timber set




bar tin

Solid, commercial tin. Bennett


Bartlett table

A three-shelf table driven by an eccentric that gives it a vanning motion.
Ore and water are fed on the upper shelf, giving two products, heads and
tailings. The latter are retreated on the second shelf, and the tailings
go to the third or lower shelf for retreatment. Liddell




Barvoys process

A sink-float process in which the medium is a suspension of clay from the
raw coal and minus 200- or 300-mesh barite in water, with the volume of
the clay usually equal to about twice that of the barite. Barite clay and
coal suspensions can be regulated to get effective washing gravities from
1.2 to 1.8. Sizes from run-of-mine to one-eighth inch may be cleaned by
this process, which has been widely adopted in Europe. Also known as the
Sophia-Jacoba process in German publications. Mitchell




barylite

An orthorhombic mineral, BaBe2 Si2 O7 ; forms hard (6
to 7 on the Mohs scale), colorless crystals; at Laangban, Sweden;
Franklin, NJ; and Park County, CO.




barysilite

A white trigonal mineral, Pb8 Mn(Si2 O7 )3 ;
occurs at Laangban, Sweden, and Franklin, NJ.




barysphere

The interior of the Earth beneath the lithosphere, including both the
mantle and the core. However, it is sometimes used to refer only to the
core or only to the mantle. Syn:centrosphere




baryta

Barium oxide; BaO. AGI




barytes

See:barite




barytocalcite

a. A monoclinic mineral, BaCa(CO3 )2 ; trimorphous with
alstonite and paralstonite.
b. A mixture of calcite and barite.




basal arkose

An arkosic sandstone basal to a sedimentary sequence, resting
unconformably on a granitic terrane; the arkosic equivalent of a granitic
basal conglomerate. AGI




basal cleavage

Mineral cleavage parallel to the basal pinacoid that is normal to the c
crystallographic axis. Also called pinacoidal cleavage.




basal conglomerate

A well-sorted, lithologically homogeneous conglomerate that forms the
bottom stratigraphic unit of a sedimentary series and that rests on a
surface of erosion, thereby marking an unconformity; esp. a coarse-grained
beach deposit of an encroaching or transgressive sea. It commonly occurs
as a relatively thin, widespread or patchy sheet, interbedded with quartz
sandstone. AGI




basal pinacoid

A pinacoid of two parallel faces that intersect only the c
crystallographic axis. Also called a base. Syn:basal plane




basal plane

a. A plane perpendicular to the c, or principal, axis in a tetragonal or
hexagonal structure. ASM, 1
b. Syn:basal pinacoid




basal reef

S. Afr. A gold-bearing reef regarded as the principal carrier of gold in
the Orange Free State. It has been associated with the Elsburg series of
the central Witwatersrand and occurs below what has become known as the
leader reef. Beerman




basalt

A general term for dark-colored mafic igneous rocks, commonly extrusive
but locally intrusive (e.g., as dikes), composed chiefly of calcic
plagioclase and clinopyroxene; the fine-grained equivalent of gabbro.
Nepheline, olivine, orthopyroxene, or quartz may be present. Adj.
basaltic. CF:tholeiite




basal thrust plane

The sole fault underlying a series of overthrusts.




basaltic

Pertaining to, made of, or resembling basalt; as, basaltic lava.
See also:basalt




basaltic dome

See:shield volcano




basaltic hornblende

A variety of hornblende containing ferric (oxidized) iron in basalts and
other basic igneous (volcanic) rocks.




basaltic layer

See:sima




basaltine

See:augite


basaluminite

A mineral, Al4 (SO4 )(OH)10 .5H2 O ; in
veinlets lining crevices in ironstone. CF:felsoebanyaite




basanite

a. An extrusive rock composed of calcic plagioclase, augite, olivine, and
a feldspathoid (nepheline, leucite, or analcime); essentially, a
feldspathoidal olivine basalt. Some basanites have been the source of
sapphires or rubies. AGI
b. A touchstone consisting of flinty jasper or finely crystalline
quartzite. Syn:touchstone; Lydian stone. AGI
c. A black variety of jasper. AGI




base

a. As used by drillers, a line of stakes set by an engineer or drill
foreman to be used as a guide to line up and point the drill in a specific
compass direction. A line in a survey which, being accurately determined
in length and position, serves as the origin for computing the distances
and relative positions of remote points and objects by triangulation.
See also:base line
b. A compound, e.g., lime, ammonia, or caustic alkali, or an alkaloid,
capable of reacting with an acid to form a salt either with or without
elimination of water.
c. Foundation or supporting structure on which a drill is mounted.
Long
d. See:basal pinacoid; base course.




base box

A unit of quantity in the tin plate trade consisting of 112 sheets
measuring 14 in by 20 in (35.6 cm by 50.8 cm) or the equivalent in area;
consequently 31,360 in2 (20.2 m2 ) of tin plate.




base bullion

Crude lead containing recoverable silver, with or without gold.
See also:work lead




base charge

a. The main explosive charge in the base of a detonator. Meyer
b. The charge loaded into the bottom of vertical holes in quarrying,
usually applicable to 3-in (7.62-cm) diameter holes and larger.
Nelson
c. The detonating component in a detonator, initiated by the priming
charge. BS, 12




base course

a. A layer of specified or selected material of planned thickness
constructed on the subgrade or subbase to serve one or more functions,
such as distributing load, providing drainage, minimizing frost action,
etc. ASCE
b. See:base




base exchange

a. The clay particle with its cations may be regarded as a kind of salt in
which the colloidal clay particle is the anion. Certain cations may
replace others, making the clay more flocculent. The cation replacement is
known as the base exchange. Syn:ion exchange; cation exchange.
AGI
b. The physicochemical process by which one species of ions adsorbed on
soil particles is replaced by another species.
See also:zeolite process




base failure

See:slope failure




base flow

Water entering drainage system from underground sources. Pryor, 3




base fracture

In quarrying, used to describe the condition of the base after a blast. It
may be a good or bad base fracture. Streefkerk




baselevel

a. The lowest level to which a land surface can be eroded by running
water. Mather
b. To reduce by erosion to or toward a baselevel. Standard, 2




baseleveled plain

A baseleveled surface is any land surface, however small, that has been
brought approx. to a baselevel, either general or local, by the process of
gradation. When such a surface has considerable extent, it becomes a
baselevel plain. Syn:peneplain




baselevel plain

A flat, comparatively featureless area or lowland, the elevation of which
cannot be materially reduced by the erosive force of running water.
AGI




base line

a. A line taken as the foundation of operations in trigonometrical and
geological surveys. See also:base
b. A surveyed line established with more than usual care, that serves as a
reference to which surveys are coordinated and correlated.
See also:base
c. The initial measurement in triangulation, being an accurately measured
distance constituting one side of one of a series of connected triangles,
and used, together with measured angles, in computing the lengths of the
other sides. AGI
d. One of a pair of coordinate axes (the other being the principal
meridian) used in the U.S. Public Land Survey system. It consists of a
line extending east and west along the true parallel of latitude passing
through the initial point, along which standard township, section, and
quarter-section corners are established. AGI
e. An aeromagnetic profile flown at least twice in opposite directions and
at the same level, in order to establish a line of reference of magnetic
intensities on which to base an aeromagnetic survey. AGI
f. The center line of location of a railway or highway; the reference line
for the construction of a bridge or other engineering structure. Sometimes
spelled: baseline. AGI




base map

a. A map on which information may be placed for purposes of comparison or
geographical correlation. Base map was at one time applied to a class of
maps now known as outline maps. It may be applied to topographic maps,
also termed "mother maps," that are used in the construction of many types
of maps by the addition of particular data. AGI
b. A map of any kind showing essential outlines necessary for adequate
geographic reference, on which additional or specialized information is
plotted for a particular purpose; esp. a topographic map on which geologic
information is recorded. AGI




basement

In geology, an underlying complex that behaves as a unit mass and does not
deform by folding. AIME, 1




basement complex

A series of rocks generally with complex structure beneath the dominantly
sedimentary rocks. In many places, these are igneous and metamorphic rocks
of either Early or Late Precambrian, but in some places these may be much
younger, as Paleozoic, Mesozoic, or even Cenozoic. See also:complex
Syn:fundamental complex




basement rock (complex)

a. A name commonly applied to metamorphic or igneous rocks underlying the
sedimentary sequence. AGI
b. Metamorphic and igneous Precambrian rocks. AGI




base metal

a. Any of the more common and more chemically active metals, e.g., lead,
copper. AGI
b. The principal metal of an alloy, e.g., the copper in brass.
CF:noble metal
c. In plural form, a classification of metals usually considered to be of
low value and higher chemical activity when compared with the noble metals
(gold, silver, platinum, etc.). This nonspecific term generally refers to
the high-volume, low-value metals copper, lead, tin, and zinc.
d. The metal base to which a coating or plating is applied.
e. The chief constituent of a metal alloy; e.g., brass is a copper-base
alloy.




base ore

Ore in which gold is associated with sulfides, as contrasted to
free-milling ores, in which the sulfides have been removed by leaching.
Newton, 1


base plug

A tapered cylinder, generally of wood, placed in a borehole and into which
a deflection drive wedge may be driven in a random or oriented position.
Syn:deflecting plug; deflection plug. Long




base price

There is a minimal market price for each metal below which it cannot fall
without putting the average producer out of business; this price has been
called the base price. Hoover




base rock

a. As used by some drillers, the solid rock immediately underlying the
overburden material. Long
b. As used by drillers in the Midwestern United States, the igneous rock
formations underlying the sedimentary rocks. Also called basement;
basement rock; pavement. Long




base station

An observation point used in geophysical surveys as a reference, to which
measurements at additional points can be compared. AGI




basic

a. Said of an igneous rock having a relatively low silica content,
sometimes delimited arbitrarily as 44% to 51% or 45% to 52% ; e.g.,
gabbro, basalt. Basic rocks are relatively rich in iron, magnesium, and/or
calcium, and thus include most mafic rocks as well as other rocks. Basic
is one of four subdivisions of a widely used system for classifying
igneous rocks based on their silica content: acidic, intermediate, basic,
and ultrabasic. CF:femic
b. Said loosely of dark-colored minerals. CF:silicic; mafic.
AGI
c. Said of a plagioclase that is calcic.




basic bottom and lining

The inner bottom and lining of a melting furnace consisting of materials
like crushed burnt dolomite, magnesite, magnesite bricks, or basic slag,
that give a basic reaction at the operating temperature. ASM, 1




basic flowsheet

A diagram of the various stages in the treatment of the raw coal in a
preparation plant, usually either a process flowsheet or an equipment
flowsheet. BS, 5




basic front

In granitization, an advancing zone enriched in calcium, magnesium, and
iron, that is said to represent those elements in the rock being
granitized that are in excess of those required to form granite. During
granitization, these elements are believed to be displaced and moved
through the rock ahead of the granitization front, to form a zone enriched
in minerals such as hornblende and pyroxene. Syn:mafic front;
magnesium front. AGI




basic grade

Used to define steel produced by the basic open-hearth process.
Hammond




basic lava

Lava poor in silica, generally less than 52% total SiO2 ; typically
dark and heavy, as basalt.




basic lining

A lining for furnaces, converters, etc., formed of nonsiliceous material,
usually limestone, dolomite, lime, magnesia, or ferrous oxide. Fay




basic lining process

An improvement of the Bessemer process in which, by the use of a basic
lining in the converter and by the addition of basic materials during the
blow, it is possible to eliminate phosphorus from the pig iron and keep it
out of the steel. Fay




basic oxygen process

A steelmaking process in which oxygen is forced at supersonic speed
through a retractable water-cooled lance, accelerating the burning off of
unwanted elements in a charge of molten iron and scrap.
Encyclopaedia Britannica




basic price

a. As used by the drilling and mining industries, a guaranteed price to be
paid for a specific quantity of materials, or type of service.
Long
b. As applied to the price of metals, it is that figure at which the price
is a minimum. See also:normal price




basic process

A steelmaking process, either Bessemer, open-hearth, or electric, in which
the furnace is lined with a basic refractory, a slag rich in lime being
formed and phosphorus removed. See also:acid process;
dephosphorization. CTD




basic refractories

Refractories that consist essentially of magnesia, lime, chrome ore, or
forsterite, or mixtures of two or more of these. Harbison-Walker




basic refractory lining

A furnace lining, composed of material low in acidic minerals, such as
silica, and high in basic minerals, such as lime, chromite, dolomite,
magnesite, and magnesia.




basic slag

Slag rich in bases, such as metallic oxides; specif., slag rich in lime,
made during the basic Bessemer or basic open-hearth steel processes, and,
from the quantity of phosphorus contained in it, valuable as an artificial
fertilizer. Standard, 2




basic solvent

One that accepts protons from solute. Pryor, 3




basic steel

Steel melted in a furnace with a basic bottom and lining and under a slag
containing an excess of a basic substance, such as magnesia or lime.
ASM, 1




basin

a. A natural depression of strata containing a coalbed or other stratified
deposit. CF:depression
b. The lowest part of a mine or area of coal lands. Hudson
c. A general region with an overall history of subsidence and thick
sedimentary section. Wheeler, R.R.


basin-and-range

Said of a topography, landscape, or physiographic province characterized
by a series of tilted fault blocks forming longitudinal, asymmetric ridges
or mountains and broad, intervening basins; specif. the Basin and Range
physiographic province in the Southwestern United States.
See also:basin range




basining

The bending down or settling of part of the Earth's crust in the form of a
basin, as by rock deformation or by solution of underground deposits of
salt or gypsum. AGI




basin range

A mountain range that owes its elevation and structural form mainly to
faulting and tilting of strata and that is flanked by alluvium-filled
basins or valleys. Etymol: from the Great Basin, a region in the
Southwestern United States characterized by fault-block mountains.
See also:basin-and-range




basis price

The price agreed between the seller and the buyer of an option at which
the option can be exercised. This price is also called the "strike price."
The price is normally the current market price of the metal.
See also:option




basket

a. A type of single-tube core barrel made from thin-wall tubing with the
lower end notched into points, which are intended to pick up a sample of
granular or plastic rock material by bending in on striking the bottom of
the borehole or a solid layer. Also used as a fishing tool to recover an
article lost or dropped into a borehole. Syn:basket core lifter;
sawtooth barrel. CF:calyx
b. Wire-mesh strainer in the top of a core barrel to strain out bits of
debris, which might clog up the water ports in the core barrelhead.
Long




basket centrifuge

A device for dewatering in which wet coal is thrown by centrifugal force
against a perforated containing surface that permits the outward passage
of water and retains the coal. BS, 5




basket core

A sample of rock or rock material recovered by using a basket tube or core
barrel. See also:basket




basket core lifter

A type of core lifter consisting of several fingerlike springs brazed or
riveted to a smooth-surfaced ring having an inside diameter slightly
larger than the core size being cut. Also called basket lifter; finger
lifter. See also:basket




basonomelane

A variety of hematite containing titanium oxide. See also:ilmenite




bass

Eng. A black carbonaceous shale, Yorkshire, Lancashire, South and North
Staffordshire. Nelson




basset

a. The outcropping edge of a geological stratum. Webster 3rd
b. The shallow or rise side of a working.
c. Coal outcrop. Pryor, 3
d. An obsolete term for the noun outcrop and the verb to crop out.
AGI




bassetite

A yellow monoclinic mineral, Fe(UO2 )2 (PO4 )2
.8H2 O ; meta-autunite group.




bastard

a. Said of an inferior or impure rock or mineral, or of an ore deposit
that contains a high proportion of noncommercial material. AGI
b. Said of any metal or ore that gives misleading assays or values.
AGI
c. Said of a vein or other deposit close to and more or less parallel to a
main vein or deposit, but thinner, less extensive, or of a lower grade.
AGI




bastard asbestos

Miners' term for picrolite (antigorite), a mineral associated in places
with chrysotile asbestos.




bastard cauk

Inferior barite; Derbyshire lead mines, U.K. Arkell




bastard emerald

See:peridot




bastard freestone

Any inferior or impure rock; the Inferior Oolite, Bath, U.K.




bastard ganister

A silica rock having the superficial appearance of a true ganister but
characterized by more interstitial matter, a greater variability of
texture, and often an incomplete secondary silicification. AGI




bastard quartz

a. See:bull quartz
b. A round or spherical boulder of quartz embedded in soft or decomposed
rock. AGI




bastard shale

See:cannel shale




bastite

An olive-green, blackish-green, or brownish variety of serpentine mineral
resulting from the alteration of orthorhombic pyroxene (esp. enstatite),
occurring as foliated masses in igneous rocks; characterized by a schiller
(metallic or pearly) on the chief cleavage face of the pyroxene.
Syn:schiller spar


bastnaesite

Alternate spelling of bastnaesite. See also:bastnasite




bastnasite

A greasy, wax-yellow to reddish-brown weakly radioactive mineral,
(Ce,La)(CO3 )F , most commonly found in contact zones, less often
in pegmatites; found associated with allanite, cerite, tysonite, fluorite,
and tornebohmite; hexagonal; obtained from Ryddarhyttan and Finbo, Sweden;
Pikes Peak, CO, and Mountain Pass, CA. Syn:bastnaesite




bastonite

A greenish-brown mica that is closely related to phlogopite.
Standard, 2




batch

A quantity of material destined for or produced by one operation.
Webster 3rd




batch charger

A mechanical device for introducing batch to the furnace.
Syn:batch feeder




batch feeder

See:batch charger
y ?
?
WÏÃ DICTIONARY TERMS:batch furnace A furnace in which each charge is pla
[\B]batch furnace[\N]




batch grinding

The grinding of a charge of mineral (dry or wet) in a closed ball mill.
Pryor, 3




batch house

The place where batch materials are received, handled, weighed, and mixed,
for delivery to melting units. ASTM




batch mill

A grinding mill, usually cylindrical, into which a charge of ore and water
is placed and is ground to completion of the required comminution.
Pryor, 3




batch sintering

Presintering or sintering in such a manner that the products are
furnace-treated in individual batches. Osborne




batch smelter

Any smelter that operates as a periodic unit, being charged, fired, and
discharged according to a predetermined cycle. See also:smelter
ASTM




batch test

A laboratory test on a small quantity of mineral under close control.
Pryor, 3




batch treatment

Treatment of a parcel of material in isolation, as distinct from the
treatment of a continuous stream of ore. Pryor, 1




bate

a. To enlarge a colliery road by lowering the floor. CF:bating
Pryor, 3
b. Eng. Cleavage in slates, esp. in the Sheerbate stone. Arkell
c. Grain, hem, secondway in other rocks. Also spelled bait. Arkell




batea

See:pan; gamella.




bate barrel

Leic. After drawing a number of barrels of water out of a sump, the first
barrel for which there is not sufficient water to fill it.




bath

a. The molten material in any furnace. Standard, 2
b. A medium such as water, air, sand, or oil for regulating the
temperature of something placed in or on it; also, the vessel containing
such a medium. Webster 3rd




batholith

A large, generally discordant plutonic mass that has more than 40 sq mi
(104 km2 ) of surface exposure and no known floor. Its formation
is believed by most investigators to involve magmatic processes. Also
spelled: bathylith. Syn:abyssolith




batholithic

Pertaining to, originating in, or derived from a batholith.




bathotonic reagent

A substance tending to diminish surface tension. See also:depressant
Nelson




bathvillite

An amorphous, opaque, very brittle woody resin; forms fawn-brown porous
lumps in torbanite; at Bathville, Scotland.


bathyal

a. Pertaining to the benthonic environment on the continental slope,
ranging in depth from 200 to 2,000 m. AGI
b. Pertaining to the bottom and overlying waters between 100 and 1,000
fathoms (600 to 6,000 ft or 183 to 1,830 m). AGI
c. Of or pertaining to the deeper parts of the ocean; deep sea.
Webster 3rd




bathyal zone

In oceanography, the slope from the continental shelf at 100 fathoms (183
m) to the abyssal zone at 1,000 fathoms (1,830 m). Also called bathyal
district. Webster 3rd




bathyclinograph

In oceanography, an instrument for measuring vertical currents in the deep
sea. Webster 3rd




bathyconductograph

A device to measure the electrical conductivity of seawater at various
depths from a moving ship. Abbrev. bc. Hy




bathygram

In oceanography, a record obtained from sonic sounding instruments.
Webster 3rd




bathylith

See:batholith




bathymeter

This instrument measures temperature, pressure, and sound velocity to
depths up to 7 miles (11.2 km). The device is completely transistorized
and uses frequency modulation for telemetering. Hunt




bathymetric

a. Relating to the measurement of depths of water in oceans, seas, and
lakes. Syn:bathymetrical
b. Relating to the contour of the bottoms of oceans, seas, and lakes.
Webster 3rd
c. Relating to the distribution in depth of marine or lacustrine
organisms. Webster 3rd




bathymetrical

See:bathymetric




bathymetric chart

Chart showing depths of water by means of contour lines or by color
shading. Hy




bathymetric contour

See:isobath




bathymetry

In oceanography, the measurement of depths of water in oceans, seas, and
lakes; also, the information derived from such measurements.
Webster 3rd




bathyorographical

In oceanography, of or relating to ocean depths and mountain heights.
Webster 3rd




bathypelagic

In oceanography, of, relating to, or living in the deeper waters of the
ocean, esp. those several hundred feet below the surface--distinguished
from abyssal and pelagic. Webster 3rd




bathyscaphe

In oceanography, a navigable submersible ship that is used for deep-sea
exploration, has a spherical watertight cabin attached to its underside,
and uses gasoline and shot for ballast. Webster 3rd




bathysmal

In oceanography, of or relating to the bottom of the deeper parts of the
sea, esp. those parts between 100 fathoms (183 m) and 1,000 (1,830 m)
fathoms deep. Webster 3rd




bathysophical

In oceanography, of or relating to a knowledge of the depths of the sea or
of the things found there. Webster 3rd




bathysphere

In oceanography, a spherical diving apparatus, made large enough to
contain two people and instruments; capable of resisting tremendous
pressure, and therefore of descending to great depths; it is used in
oceanography for the investigation of deepwater faunas. CTD




bathysystem

A coined word for a permanent sea floor installation. Hunt




bathythermogram

In oceanography, a record obtained with a bathythermograph.
Webster 3rd




bathythermograph

An instrument, which may be lowered into the sea from a vessel at anchor
or underway, to record temperature as a function of depth. The
temperature-sensing device is a Bourdon tube, the depth finder is a
bellows system. Accuracy of temperature is + or - 0.1 degrees F (+ or -
0.056 degrees C); depth + or - 10 ft (3.0 m). Abbrev. bt. Hy


bathythermosphere

In oceanography, a bathythermograph. Webster 3rd




bathyvessel

In oceanography, a ship (as a submarine or bathysphere) designed for
exploration of or navigation in water far below the surface of a sea or
lake. Webster 3rd




bating

Eng. Lowering a drift or road. See also:bate




batten

a. A strip of wood used for nailing across two other pieces (as to hold
them together or to cover a crack). Webster 3rd
b. A piece of square-sawn converted timber, between 2 in and 4 in (5.1 and
10.2 cm) in thickness and from 5 to 8 in (12.7 to 20.3 cm) in width. Used
for flooring or as a support for laths. CTD
c. A bar fastened across a door, or anything composed of parallel boards
to secure them and to add strength and/or reduce warping. CTD




batter

a. Recessing or sloping a wall back in successive courses; opposite of
corbel. ACSG, 1
b. A paste of clay or loam. Webster 2nd
c. The inward slope from bottom to top of the face of a wall.
Nichols, 1
d. A pile driven at an angle to widen the area of support and to resist
thrust. Nichols, 1




batter boards

Horizontal boards placed to mark a line and a grade of a proposed building
or slope. Nichols, 1




battered set

A set of mine timbers in which the posts are inclined.




batter level

An instrument for measuring inclination from the vertical.
Standard, 2




battery

a. See:blasting machine; exploder. Nelson
b. A number of similar machines or similar pieces of equipment placed side
by side on a single or separate base and by means of common connections as
a unit. Long
c. Mine support in which timbers are placed in groups of 3 to 12 or more.
The battery may be strengthened by binding with wire. Spalding
d. A wooden platform for miners to stand upon while at work, esp. in
steeply dipping coal beds.
e. A series or row of coke ovens. Mersereau, 2
f. A bulkhead or structure of timber for keeping coal in place.
Hess
g. The plank closing the bottom of a coal chute.
h. A series of stamps, usually five, operated in one box or mortar, for
crushing ores; also, the box in which they are operated. Hess
i. A stamper mill for pulverizing stone. Gordon
j. Timbering in which the sticks are placed from foot to hanging wall,
touching each other, in a solid mass of 3 to 12 or more. The battery may
be further strengthened by binding around with wire. Spalding
k. In steeply pitching seams, a wooden structure built across the chute to
hold back blasted coal. Korson
l. A number of stamps for crushing and pulverizing ores. Nelson
m. Section of ore dressing (reduction) plant. Pryor, 3
n. A combination of chemically activated accumulators, which, after
charging, may be used for a considerable time as a source of
direct-current electricity. Also called storage battery. Long




battery charging station

See:locomotive garage




battery of holes

A number of charges, in drill holes, fired simultaneously with an electric
current. Also called multiple shot. Fay




battery of ovens

A row or group of ovens for making coke from coal.




battery ore

A type of manganese ore, generally a pure crystalline manganese dioxide
(pyrolusite or nsutite), that is suitable for use in dry cells.
AGI




battery starter

In anthracite and bituminous coal mining, one who charges and sets off
explosives in large lumps of coal or where these lumps have accumulated
and blocked the flow of coal down chutes from the storage structures
(batteries). Also called batteryman; chute tender; starter. DOT




battery starting

The use of unconfined explosives to start the flow of coal down a breast
or chute in an anthracite mine. CFR, 4




baulk

A beam. Mason




Baume gravity

Designating or conforming to either of the scales used by the French
chemist, Antoine Baume (1728-1804). One scale, which is used with liquids
heavier than water, sinks to 0 degrees (B or Be, symbols for Baume) in
pure water and to 15 degrees (B or Be) in a 15% salt solution. The other
scale, for liquids lighter than water, sinks to 0 degrees (B or Be) in a
10% salt solution and to 10 degrees (B or Be) in pure water.
Webster 2nd




baumhauerite

A lead- to steel-gray triclinic mineral, Pb3 As4 S9 .




Baum jig

A washbox in which the pulsating motion is produced by the intermittent
admission of compressed air to the surface of the water following a
principle introduced by Baum. Also called Baum box; Baum-type washbox.
See also:jig




baum pot

a. A cavity left in roof strata over coal as a result of the dropping
downward of a cast of a fossil tree stump after removal of the coal.
AGI
b. Eng. Nodule in the roof of the Halifax hard bed coal. CF:potlid
Arkell




Baum washer

See:Baum jig


bauxite

An off-white, grayish, brown, yellow, or reddish brown rock composed of
amorphous or microcrystalline aluminum oxides and oxyhydroxides, mainly
gibbsite Al(OH)3 , bayerite Al(OH)3 , boehmite
AlO(OH) , and diaspore AlO(OH) admixed with free silica, silt, iron
hydroxides, and esp. clay minerals; a highly aluminous "laterite." It is
massive, pisolitic, earthy; occurs as weathered surface deposits after
prolonged leaching of silica from aluminous rocks under tropical to
subtropical weathering, also transported deposits. Bauxite is the chief
ore of aluminum.




bauxite brick

A firebrick composed essentially of hydrated alumina and ferric oxide.
Such bricks are used for the lining of furnaces where a neutral material
is required. Osborne




bauxite cement

A cement made from bauxite and lime in an electric furnace; it hardens
rapidly. Sometimes called ciment fondu. Nelson




bauxite pneumoconiosis

Found in workers exposed to fumes containing aluminum oxide and minute
silica particles arising from smelting bauxite in the manufacture of
corundum. Syn:Shaver's disease




bauxitic

Containing much bauxite; e.g., a bauxitic clay containing 47% to 65%
alumina on a calcined basis, or a bauxitic shale abnormally high in
alumina and notably low in silica. AGI




bauxitic clay

a. A clay consisting of a mixture of bauxitic minerals, such as gibbsite
and diaspore, with clay minerals, the former constituting not over 50% of
the total. The opposite of this would be an argillaceous bauxite.
ACSB, 1
b. A natural mixture of bauxite and clay, containing not less than 47% nor
more than 65% alumina on a calcined basis. Harbison-Walker




bauxitization

Development of bauxite from primary aluminum silicates (such as feldspars)
or from secondary clay minerals under aggressive tropical or subtropical
weathering conditions of good surface drainage, such as the dissolving
(usually above the water table) of silica, iron compounds, and other
constituents from alumina-containing material. AGI




bavenite

A white hydrous silicate of aluminum, calcium, and beryllium, Ca4
Be2 Al2 Si9 O26 (OH)2 ; orthorhombic;
earthy, radiating fibrous; platy prismatic crystals. From Baveno, Italy;
Mesa Grande, CA. English




b axis

One of the three crystallographic axes used as reference in crystal
description. It is oriented horizontally, right to left. The letter b
usually appears in italics. CF:a axis; c axis.




bay

a. An open space in a mine for storage of equipment, conducting repairs,
or disposal of waste.
b. A recess in the shore or an inlet of a sea or lake between two capes or
headlands, not as large as a gulf, but larger than a cove. Hunt
c. A portion of the sea that penetrates into the interior of the land. It
is usually wider in the middle than at the entrance. It may be similar to
a gulf, but smaller. Hunt
d. A portion of the sea partly surrounded by ice. Hunt
e. The discharge point of a hopper, usually applied to coal or ore hopper
rail cars.




bayerite

A dimorph of gibbsite, long known as a synthetic product, now found as a
naturally occuring mineral, Al(OH)3 , from Portole, Istria. The
naturally occurring bayerite from Fenyoro, Hungary, was found by X-ray
study to be gibbsite. Am. Mineral., 1; Am. Mineral., 1




Bayer process

A process for extracting alumina from bauxite ore before the electrolytic
reduction of alumina. ASM, 1




bayldonite

A monoclinic mineral, PbCu3 (AsO4 )2 (OH)2 .H
2 O ; forms minute grass-green to blackish-green mammillary masses;
in Cornwall, U.K.




bayleyite

A yellow monoclinic mineral; Mg2 (UO2 )(CO3 )3
.18H2 O ; radioactive.




bay salt

A coarse-grained variety of common salt obtained by evaporating seawater
in shallow bays or pits by the heat of the sun. Standard, 2




bazzite

A hexagonal mineral, Be3 (Sc,Al)2 Si6 O18 ;
the scandium analog of beryl; blue; at Baveno, Italy; Val Strem,
Switzerland; and in central Kazakhstan.




bc-joint

See:longitudinal joint




b direction

See:b axis




beach concentrate

A natural accumulation in beach sand of heavy minerals selectively
concentrated (by wave, current, or surf action) from the ordinary beach
sands in which they were originally present as accessory minerals; esp. a
beach placer. See also:beach placer




beach deposit

Concentrations of mineral formed by the grinding action of natural forces
(wind, wave, or frost) and the selective transporting action of tides and
winds. Pryor, 3




beach drift

The movement of material along the shore by the action of the uprush and
backwash of waves breaking at an angle with the shore.
Syn:longshore drift


beach mining

The exploitation of the economic concentrations of the heavy minerals
rutile, zircon, monazite, ilmenite, and sometimes gold, which occur in
sand dunes, beaches, coastal plains, and deposits located inland from the
shoreline. High-grade concentrate is usually obtained from low-grade
material by the use of suction dredges and spiral concentrators.
Nelson




beach ore

See:beach placer




beach placer

A placer deposit on a present or ancient sea beach. There may be a series
of paleo-beach placers owing to changes of shoreline.
See also:black sand; placer; beach concentrate. Syn:beach ore




beach ridge

A low, essentially continuous mound of beach or beach-and-dune material
(sand, gravel, shingle) heaped up by the action of waves and currents on
the backshore of a beach beyond the present limit of storm waves or the
reach of ordinary tides, and occurring singly or as one of a series of
approx. parallel deposits. The ridges are roughly parallel to the
shoreline and represent successive positions of an advancing shoreline.
AGI




bead

a. The globule of precious metal obtained by the cupellation process in
assaying. Webster 3rd
b. In blowpipe analysis of minerals, a drop of a fused material, such as a
"borax bead," used as a solvent in color testing for various metals. The
addition of a metallic compound to the bead will cause the bead to assume
the color that is characteristic of the metal. See also:blowpiping
AGI




beads

In ion exchange, sized resin spheres, usually +20 mesh, so constituted as
to capture ions from pregnant solutions under stated loading conditions
and to relinquish them under other (eluting) conditions. Two types are
anionic and cationic. See also:resin




bead tests

In mineral identification, borax or other flux is fused to a transparent
bead by heating in a blowpipe or other flame in a small loop formed from
platinum wire. When suitable minerals are flux melted in this bead,
characteristic glassy colors are produced in an oxidizing or reducing
flame and serve to identify specific chemical elements.




beaker decantation

A method of sizing finely ground, insoluble, homogeneous material or
classifying ore particles. A weighed quantity is dispersed in liquid and
allowed to settle for a timed period, a liquid fraction then being
decanted. The treatment is repeated several times, the settled fraction
now representing one size group (if homogeneous) or settled group (if
minerals of various densities are present). The decanted fluid is
similarly treated for progressively lengthened settling periods.
Pryor, 3




beam

a. A bar or straight girder used to support a span of roof between two
support props or walls. See also:crossbar
b. The walking beam; a bar pivoted in the center, which rocks up and down,
actuating the tools in cable-tool drilling or the pumping rods in a well
being pumped. Hess




beam action

In crushing, seizure of rock slab between approaching jaws so as to
present crushing stress above unsupported parts of the rock, thus inducing
shear failure rather than failure under compression. Pryor, 3




Beaman stadia arc

A specially graduated arc attached to the vertical circle of an alidade or
transit to simplify the computation of elevation differences for inclined
stadia sights (without the use of vertical angles). The arc is so
graduated that each division on the arc is equal to 100 (0.5 sin 2A),
where A is the vertical angle. Named after William M. Beaman (1867-1937),
U.S. topographic engineer, who designed it in 1904. AGI




beam building

A process of rock bolting in flat-lying deposits where the bolts are
installed in bedded rock to bind the strata together to act as a single
beam capable of supporting itself and thus stabilizing the overlying rock.
Lewis




beam compass

An instrument for describing large arcs. It consists of a beam of wood or
metal carrying two beam heads, adjustable for position along the beam, and
serving as the marking points of the compass. Syn:trammel




beam engine

An early type of vertical steam engine. It operated the Cornish pump.
Nelson




bean ore

A loose, coarse-grained pisolitic iron ore; limonite occurring in
lenticular aggregations. See also:pea ore




bean rock

Shingle cemented by tufa, Ventnor, U.K.




beans

A cleaned and screened anthracite product 7/8 in by 3/8 in (22.2 mm by 9.5
mm). Nelson




bear

a. To bear in; underholing or undermining; driving in at the top or at the
side of a working.
b. Eng. A calcareous or clay ironstone nodule, Derbyshire. Arkell
c. The mass of iron, which, as a result of wear of the refractory
brickwork or blocks in the hearth bottom of a blast furnace, slowly
replaces much of the refractory material in this location.
Syn:salamander




bearer

Eng. A band of hard limestone consisting of numerous stromatoporoids,
mainly a ramose species, Wenlock Limestone, Dudley. Arkell




bearer bar

One of the bars that support the grate bars in a furnace. Fay




bearers

Heavy timbers placed in a shaft at intervals of 30 to 100 ft (9.1 to 30.5
m) to support shaft sets. They are usually put beneath the end plates and
dividers, and rest in hitches cut in the wall. Also used to support
pumping gear. Syn:biard


bearing

a. The part of a beam or girder that actually rests on the supports.
CTD
b. Undercutting the coal face by holing. Nelson
c. The horizontal angle between the meridian (true or magnetic) and any
specified direction. The angle is measured from either the north or the
south point, as may be required to give a reading of less than 90 degrees
, and the proper quadrant is designated by the letter N or S, preceding
the angle, and the letter E or W, following it; as, N. 80 degrees E.
CF:azimuth
d. The points of support of a beam, shaft, or axle, i.e., bearing points.
e. The direction of a mine drivage usually given in terms of the
horizontal angle turned off a datum direction, such as the true north and
south line. Nelson
f. In Texas land surveys, a reference point to identify a land corner or a
point on a survey line. Seelye, 2
g. A part in which a shaft or pivot revolves. Nichols, 1
h. See:ball bearing




bearing bed

A bed that contains, or is likely to contain, ore minerals; one that is
productive as opposed to dead or barren. Arkell




bearing capacity

a. The load-per-unit area that the soil or solid rock can support without
excessive yield. See also:foundation investigation
b. See also:ultimate bearing capacity




bearing door

A door so placed as to direct and regulate the amount of air current
necessary for the proper ventilation of a district of a mine.
See also:separation door




bearing-in

The depth of an undercut, or holing, from the face of the coal to the end
of the undercut. Fay




bearing-in shots

Boreholes tending to meet in the body of the rock; intended to unkey the
face when charged and fired. Stauffer




bearing plate

A plate of the thickness and area required to distribute a given load,
such as a plate under a beam flange resting on a wall. If the plate is 2
in (5.1 cm) or more in thickness, it is called a slab. Crispin




bearing pressure

The load on a bearing surface divided by the area upon which it rests.
Hammond




bearing set

In a mine shaft, a specially substantial set of timbers used at intervals
to support the linings and ordinary bearers. They are tied into the
surrounding rock to give extra strength.




bearing stake

A stake set on a line to indicate the horizontal direction an inclined
borehole is to be drilled. Long




bearing stratum

The earth formation that has been selected as the most suitable to support
a given load. Hammond




bearing strength

The maximum bearing load at failure divided by the effective bearing area.
In a pinned or riveted joint, the effective area is calculated as the
product of the diameter of the hole and the thickness of the bearing
member. ASM, 1




bearsite

A monoclinic mineral, Be2 (AsO4 )(OH).4H2 O .




bears' muck

Eng. Soft, bluish earth. Used by well sinkers in Cambridgeshire and
Huntingdonshire. See also:caballa ball




beater

A laborer who shovels or dumps asbestos fibers and sprays them with water
to prepare them for the beating process that reduces fibers to pulp for
making asbestos paper. DOT




beater mill

Mill used for impact crushing of easily broken minerals. An armature
carrying swinging hammers, plates, or disks hits the falling stream of
rock, dashing particles against one another and against the casing of the
mill. See:hammermill




beaverite

A trigonal mineral, Pb(Cu,Fe,Al)3 (SO4 )2 (OH) (sub
6) ; canary yellow; in minute plates; in Beaver County, UT.




Becke line

In the "Becke test" a bright line, visible under a microscope under plane
polarized light, that separates substances of different indices of
refraction.




beckerite

a. A brown resin, occurring with amber. English
b. A brown variety of retinite having a very high oxygen content (20% to
23%).




Becke test

In polarized-light microscopy, a method or test for determining relative
indices of refraction between two adjacent mineral grains or between a
mineral grain and its host medium; e.g., Canada balsam, Lakeside cement,
an epoxy resin, or an immersion oil of known index of refraction. On
defocusing by increasing the working distance between the microscope stage
and the objective lens, the Becke line moves toward the higher index of
refraction. CF:van der Kolk method




Becorit system

An overhead monorail system. See also:monorail


becquerelite

An orthorhombic mineral, Ca(UO2 )6 O4 (OH)6
.8H2 O , with barium and potassium substitution for calcium;
amber-yellow; a radioactive product of uraninite and ianthinite
alteration.




bed

a. The smallest distinctive division of a stratified series, marked by a
more or less well-defined surface or plane from its neighbors above and
below; a layer or stratum. Fay
b. A deposit, as of ore, parallel to the stratification.
Standard, 2
c. A bed (or beds) is the smallest formal lithostratigraphic unit of
sedimentary rocks. The designation of a bed or a unit of beds as a
formally named lithostratigraphic unit generally should be limited to
certain distinctive beds whose recognition is particularly useful.
Coalbeds, oil sands, and other beds of economic importance commonly are
named, but such units and their names usually are not a part of formal
stratigraphic nomenclature (NACSN, 1983, Art. 26).
d. That portion of an outcrop or face of a quarry that occurs between two
bedding planes. Fay
e. The level surface of rock upon which a curb or crib is laid.
Fay
f. All the coal, partings, and seams that lie between a distinct roof and
floor. Hess
g. Perhaps the most common term in geology, meaning layer or stratum.
Quarrymen usually mean by beds not the stone beds in the geologist's sense
but the partings between them. Arkell
h. A stockpile, as of ore, concentrates, and fluxes, built up of
successive layers so that transverse cutting yields a uniform mixture for
furnace feed until the material is all consumed.
i. In mineral processing, a heavy layer of selected oversized mineral or
metal shot maintained on screen of jig. Pryor, 3
j. That part of conveyor upon which the load or carrying medium rests or
slides while being conveyed.
k. In bulk material conveyors, the mass of material being conveyed.
l. A base for machinery. Nichols, 1




bed claim

Aust. A mining claim lying on the bed of a stream.




bedded

Applied to rocks resulting from consolidated sediments and accordingly
exhibiting planes of separation designated bedding planes. Fay




bedded deposit

a. A term usually applied to mineral deposits that are found parallel with
the stratification of sedimentary rocks and usually of contemporaneous
origin. The term is used to describe layerlike deposits of replacement
origin. See also:bedded formation
b. Syn:blanket deposit




bedded formation

A formation that shows successive beds, layers, or strata owing to the
manner in which it was formed. See also:bedded deposit




bedded rock

One of the two subdivisions of competent rock. To be classed as bedded
rock, the rock within each bed, in addition to being elastically perfect,
isotropic, and homogeneous, must have a bed thickness that is small
compared with the roof span, and the bond between beds must be weak. Most
sedimentary rocks and some stratified metamorphic rocks fall in this
group.




bedding

a. A quarry term for a structure occurring in granite and other
crystalline rocks that tend to split in well-defined planes more or less
horizontal or parallel to the land surface. Syn:sheeting
Wheeler, R.R.
b. The storing and mixing of different ores in thin layers in order to
blend them more uniformly in reclamation. AGI
c. The layer of heavy and oversized material placed above the screen in
jigging. Also called ragging. Pryor, 4
d. Pieces of soft metal placed under or around a handset diamond as a
cushion or filler. Also called backing; calking. Long
e. Ground or supports in which pipe is laid. Nichols, 1
f. The arrangement of a sedimentary rock in beds or layers of varying
thickness and character; the general physical and structural character or
pattern of the beds and their contacts within a rock mass, such as
cross-bedding and graded bedding; a collective term denoting the existence
of beds. Also, the structure so produced. The term may be applied to the
layered arrangement and structure of an igneous or metamorphic rock.
See also:stratification
AGI
g. The initial filling of a thickener for continuous operation.




bedding cleavage

Cleavage that is parallel to the bedding. Billings




bedding down

Formation of layer of valueless and inert rock at points in a new flowline
where material will settle from the stream of ore being treated, for
example, between bottom of thickener and its rakes. Pryor, 3




bedding fault

A fault that is parallel to the bedding. AGI




bedding fissility

A term generally restricted to primary foliation parallel to the bedding
of sedimentary rocks; i.e., it forms while the sediment is being deposited
and compacted. It is the result of the parallelism of the platy materials
to the bedding plane, partly because they were deposited that way and
partly because they were rotated into this position during compaction.
AGI




bedding glide

Overthrusting in which a bed, such as a coal seam, is disrupted and thrust
laterally along the roof or floor parting, giving a duplication of coal.
Nelson




bedding joint

a. A thin layer differing in composition with the beds between which it
occurs. Schieferdecker
b. A joint parallel to the bedding planes formed by tectonic processes.
Schieferdecker




bedding plane

a. In sedimentary or stratified rocks, a surface that separates each layer
from those above or below it. It usually records a change in depositional
circumstances by grain size, composition, color, or other features. The
rock may tend to split or break readily along bedding planes.
See also:plane
b. Surface on which rock-forming mineral has been deposited.
Syn:bedding
c. A separation or weakness between two layers of rock caused by changes
during the building up of the rock-forming material.
See also:bed joint




bedding thrust

A thrust fault that is parallel to the bedding. Billings




bede

A miner's pick. Pryor, 3




Bedford limestone

One of the finest and best known building stones to be found in the United
States. It gets its name from its shipping point, Bedford, IN.
Crispin




bed joint

a. A horizontal crack or fissure in massive rock.
See also:bedding plane
b. One of a set of cracks or fissures parallel with the bedding of a rock.
Webster 3rd
c. A horizontal joint between courses of brick. ARI
d. The horizontal layer of mortar on (or in) which a masonry unit is laid.
ACSG, 1




bedrock

a. Solid rock exposed at the surface of the Earth or overlain by
unconsolidated material, weathered rock, or soil.
b. In Australia, the stratum upon which the wash dirt rests is usually
called bedrock. It usually consists of granite or boulder clay (glacial)
and, much more rarely, basalt. When the stratum consists of slates or
sandstones (Silurian or Ordovician), it is usually called reef rock.
Eng. Min. J., 1
c. A general term for the rock, usually solid, that underlies soil or
other unconsolidated, superficial material. A British syn. of the
adjectival form is "solid," as in solid geology. See:stonehead
AGI
d. See:bottom rock; rock base.




bedrock test

A borehole drilled to determine the character of bedrock and the character
and depth of overburden overlying such bedrock. Syn:testing bedrock
Long


bed separation

The thin cavities formed along bedding planes due to differential lowering
of strata over mine workings; e.g., a shale with its greater bending
capacity will subside and separate from a higher bed of sandstone. Roof
supports are so set as to keep bed separation to a minimum. Nelson




bed vein

A vein following the bedding in sedimentary rocks, or a mineralized
permeable stratigraphic zone below an impervious bed. CF:blanket vein;
manto; sheet ground.




beech coal

Charcoal made from beechwood.




beeches

Scot. Strips of hardwood fastened to pump rods to save them from wear at
the collars. Fay




beef

A quarry worker's term, used originally in Purbeck, southern England, for
thin, flat-lying veins or layers of fibrous calcite, anhydrite, gypsum,
halite, or silica, occurring along bedding planes of shale, giving a
resemblance to beef. It appears to be due to rapid crystallization in
lenticular cavities. See also:bacon




beehive coke

Coke manufactured in beehive, rectangular, or similar forms of ovens in a
horizontal bed, where heat for the coking process is secured by combustion
within the oven chamber. ASTM




beehive coke oven

A coke oven with a brick bottom, side walls, and a domed roof.




beehive kiln

An intermittent kiln, circular in plan, with fireboxes arranged around the
circumference. Such kilns find use in the firing of blue engineering
bricks, pipes, some refractory bricks, etc. Syn:round kiln
Dodd




Beethoven exploder

A machine for the multishot firing of series-connected detonators in
tunneling and quarrying. See also:exploder




beetle stone

A nodule of coprolitic ironstone, so named from the resemblance of the
enclosed coprolite to the body and limbs of a beetle. Syn:septarium
Fay




beetling stones

Flat rocks on which clothes were beetled (stamped or pounded).




before breast

A miner's term for that part of the orebody that still lies ahead.
See also:breast




beidellite

A monoclinic mineral, (Na,Ca0.5 )0.3 Al2 (Si,Al) (sub
4) O10 (OH)2 .nH2 O ; smectite group; aluminum rich
and poor in magnesium and iron; a common constituent of soils and certain
clay deposits (e.g., metabentonite). CF:montmorillonite




Beien kep gear

An improved type of kep in which the kep shoes are withdrawn without
previously raising the cage and thus reducing the decking time. The
operation may be automatic, except for cage release, because the
arrangement allows the kep shoes to trip without the position of the hand
lever being altered. See also:kep




Beien machine

A pneumatic stowing machine that consists of a paddle wheel with six
compartments working inside an adjustable airtight casing. This wheel is
driven at a speed of 15 to 30 rpm by means of an air turbine through
gearing. Two sizes of Beien machines are used having capacities of 30 yd
3 and 60 yd3 (22.9 m3 and 45.9 m3 ) of
stowing material per hour, respectively. The dirt falls from the paddle
wheel into the airstream in the pipe underneath the paddle box and passes
along 6-in (15.2-cm) diameter pipes to the outlet, where a detachable
deflector guides the stream of dirt into the required place in the pack
hole. Mason




Beilby layer

Flow layer resulting from incipient fusion during polishing of mineral
surface, and therefore not characteristic of true crystal structure.
Pryor, 1




Belfast truss

A bowstring design of girder fabricated entirely from timber components.
Hammond




Belgian coke oven

A rectangular variation of the beehive coke oven.
See also:Belgian oven




Belgian effective temperature

A temperature scale used in Belgium for measuring the environmental
comfort in mines. Roberts, 1




Belgian oven

A rectangular oven with end doors and side flues for the manufacture of
coke. See also:Belgian coke oven




Belgian press

See:double-roll press


Belgian process

A process (no longer used) to smelt zinc in which roasted zinc ore is
mixed with a reducing material, such as coal or coke, placed in
cylindrical retorts, and heated in a furnace, such that the escaping zinc
vapor is condensed from the open end of the retort. Fay




Belgian silex

A very hard, tough, more or less cellular quartzite resembling French
buhrstone and the most favored natural mill-lining material for most
purposes. It is imported in rectangular blocks that are more or less
shaped to fit the curve of a mill. AIME, 1




Belgian zinc furnace

A furnace in which zinc is reduced and distilled from calcined ores in
tubular retorts. These furnaces may be classified as direct fired and gas
fired, but there is no sharp division between these systems, which merge
into one another by difficultly definable gradations. Each class of
furnace may be subdivided into recuperative and nonrecuperative, but heat
recuperation in connection with direct firing is rare.




belgite

See:willemite




belite

a. A constituent of portland cement clinkers. English
b. A calcium orthosilicate found as a constituent of portland-cement
clinkers; specif. larnite. Syn:felite




belith

Original spelling of belite. Hey, 1




Belknap chloride washer process

This coal washer uses a calcium chloride solution of a comparatively low
density and depends on mechanically induced upward currents to obtain a
separation at the desired specific gravity. It produces a clean, dustless,
nonfreezing coal. Mitchell




bell

a. A cone-shaped mass of ironstone or other substance in the roof of a
coal seam. Bells are dangerous as they tend to collapse suddenly and
without warning. See also:pot bottom
b. A gong used as a signal at mine shafts.
c. See:cone




bellan

a. Eng. Dusty lead ore. Arkell
b. A form of lead poisoning to which miners are subject. Also spelled
belland; bellund.




belland

See:bellan




bell and hopper

See:cup and cone




bellcrank drive

A device used to drive an auxiliary shaker conveyor without changing the
direction of the main conveyor. It consists essentially of two driving
arms, placed at right angles to each other and supported at their pivot
point by a fulcrum jack. When these driving arms are attached to the main
and auxiliary conveyors, the reciprocating motion of the main conveyor is
transmitted to the auxiliary conveyor, which can then discharge its load
onto the main conveyor. Jones, 1




belled

Eng. Widened; said of the enlarged portion of a shaft at the landing for
running the cars past the shaft, and for caging.




bell holes

A conical cavity in a coal mine roof caused by the falling of a large
concretion; or, as of a bell mold.




bellies

Widenings in a vein. See also:belly




bellingerite

A triclinic mineral, Cu2 (IO3 )6 .2H2 O ;
forms light green or bluish green crystals; at Chuquicamata, Chile.




bellite

a. An explosive consisting of five parts of ammonium nitrate to one of
metadinitrobenzene, usually with some potassium nitrate. Fay
b. A lead chromo-arsenate in delicate velvety, red to orange tufts.
Webster 2nd




bell jar

See:jar collar




bell-metal ore

Corn. An early name for tin pyrite (stannite), so called because of its
bronze color. See also:stannite




bell mold

Som. A conical-shaped patch of a mine roof, probably originating with the
fossils called sigillaria, or the roots of trees. Syn:caldron
See also:bell; caldron bottom. Fay




bellows

a. An instrument with an air chamber and flexible sides used for
compressing and/or directing a current of air. Crispin
b. An expansible metal device containing a fluid that will volatilize at
some desired temperature, expand the device, and open or close an opening
or a switch; used in controls and steam traps. Strock, 2


bell pit mining

Obsolete method of winning coal or bedded iron from shallow deposits, in
which mineral was extracted and dragged to a central shaft.
Pryor, 3




Bell process

See:Bell's dephosphorizing process




bell screw

An internally threaded bell-shaped iron bar for recovering broken or lost
rods in a deep borehole. Syn:box bell; screw bell; bell tap.
Fay




Bell's dephosphorizing process

The removal of phosphorus from molten pig iron in a puddling furnace lined
with iron oxide and fitted with a mechanical rabble to agitate the bath.
Red-hot iron ore is added. See also:Krupp washing process
Syn:Bell process




bell sheave

Aust. A sheave in the shape of a truncated cone used in connection with
the main-and-tail system of rope haulage at curves, so as to keep the rope
close to the ground. Fay




bell socket

See:bell tap; screw bell.




bell tap

A cylindrical fishing tool having an upward-tapered inside surface
provided with hardened threads. When slipped over the upper end of lost,
cylindrical, downhole drilling equipment and turned, the threaded inside
surface of the bell tap cuts into and grips the outside surface of the
lost equipment. Also called bell; box bill; die; die collar; die nipple.
See also:bell screw; screw bell; die. Syn:bell socket; outside tap.
Long




bell top

Term used to describe a good roof that has a clear ringing sound.
Kentucky




bellund

See:bellan




bell work

a. Derb. A system of working an ironstone measure by upward underground
excavations around the shafts (raises) in the form of a bell or cone.
Fay
b. A method used in working salt deposits. Standard, 2




belly

a. See:pocket
b. A bulge, or mass of ore in a lode. Fay
c. Widened places in a borehole caused by sloughing of loose material from
the borehole sidewalls. See also:bellies




belly pipe

A flaring-mouthed blast pipe in an iron furnace. Standard, 2




Belomorite

Trade name for moonstone from the White Sea. Spencer, 3




belonesite

A white, transparent magnesium molybdate, MgMoO4 , crystallizing in
the tetragonal system. Fay




belonite

An elongated or acicular crystallite having rounded or pointed ends.
AGI




belovite

A hexagonal mineral, (Sr,Ce,Na,Ca)5 (PO4 )3 (OH) ;
apatite group; occurs in pegmatites.




belt

a. See:link-plate belt
b. Can. Regional surface zone along which mines and prospects occur.
Hoffman
c. A continuous strap or band for transmitting power from one wheel to
another, or (rarely) to a shaft, by friction.
See also:stitched canvas conveyor belt
d. A zone or band of a particular kind of rock strata exposed on the
surface. CF:zone
e. An elongated area of mineralization. AGI




belt capacity

The load that a belt conveyor is able to carry, depending upon the area of
cross section of load on belt and the speed of the belt. Nelson




belt cleaner

A device attached to a belt conveyor to clean or remove dirt or coal dust
from the belt surface. Rotary bristle brushes are sometimes used, driven
either by gearing from the conveyor or by an independent high-speed motor.
Another device consists of a short scraper conveyor with rubber-faced
scrapers attached at intervals. The scraper belt is driven via a chain
drive from the main conveyor drum. Nelson




belt conveyor

a. A moving endless belt that rides on rollers and on which materials can
be carried. The principal parts of a belt conveyor are (1) a belt to carry
the load and transmit the pull, (2) a driving unit, (3) a supporting
structure and idler rollers between the terminal drums, and (4)
accessories, which include devices for maintaining belt tension and
loading and unloading the belt, and equipment for cleaning and protecting
the belt. See also:hatch conveyor; underground mine conveyor.
Kentucky; Nelson
b. See:troughed belt conveyor




belt conveyor structure

The framework for supporting the bottom strand of a belt conveyor.
Nelson


belt creep

Gentle slip. Pryor, 3




belt dressing

A compound used to improve adhesion or flexibility. Pryor, 3




belt feeder

Short loop of conveyor belt, or articulated steelplate, used to draw ore
at a regulated rate from under a bin or stockpile. Pryor, 3




belt flotation

A method sometimes used to recover diamond particles 1 mm or smaller.




belt friction

See:friction




belt horsepower

That power developed with all auxiliary equipment (such as pump and fans)
attached; it is consequently lower than flywheel horsepower.
Carson, 1




belting

One of the main parts of a belt conveyor. The belting consists of piles of
cotton duck impregnated with rubber, with top and bottom covers of rubber.
The carrying capacity of the belt will vary, depending on the running
speed and the width of the belt. Sinclair, 5




belt loader

A machine whose forward motion cuts soil with a plowshare or disk and
pushes it to a conveyor belt that elevates it to a dumping point.
Syn:elevating grader




beltman

See:conveyor man




belt of variables

The belt of marine deposition extending from the coast (high watermark) to
a depth of about 100 fathoms (183 m); i.e., corresponding roughly with the
continental shelf (in the wide sense, to include the shore); passing into
the mud belt at the inner mud line. Challinor




belt press

A device for dewatering mineral slurries, esp. waste from coal washing,
which consists of a moving belt constructed of relatively open cloth. Belt
presses are widely used in the minerals industry.




belt protection device

A device fitted to a belt conveyor to give an alarm or to cause the
conveyor to stop in the event of a defect, such as belt slip, breakage,
tearing, misalignment, or overload. BS, 13




belt slip

The difference in speed between the driving drum and the belt conveyor.




belt table

A table incorporating a belt conveyor so arranged as to provide working
space on one or both sides of the belt.




belt tensioning device

A device fitted to a belt conveyor that automatically takes up any slack
or stretch in the belting. A gravity takeup device is sometimes fitted
immediately behind the driving unit, thus eliminating slack that would
otherwise occur. The main disadvantage of gravity takeup is that it gives
the belt three entire bends. Nelson




belt tripper

A device or mechanism that causes the conveyor belt to pass around pulleys
for the purpose of discharging material from it.




belt-type conveyor

A conveyor consisting of an endless belt used to transport material from
one place to another.




Belugou imperfection coefficient

In coal testing, a parameter, B, applied to the ash curve: B = (p75 -
p25)/2(p50 - 1), where pX is the specific gravity of particles of which
the fraction separated is X percent, (p75 - p25) is the statistical
intermediate or inquartile range, and p50 is the effective density of
separation in a process in which a dense medium, vertical current, or
jigging action is used. Equation is used to define shape of a Tromp curve.
Pryor, 3




belyankinite

A mineral, Ca1-2 (Ti,Zr,Nb)5 O12 .9H2 O(?) ;
amorphous, yellowish-brown.




Belynski's reagent

A 1% copper sulfate solution recommended as an etchant for revealing
dendritic structures in high-carbon steels. Osborne




bementite

a. A light gray or grayish-brown, common manganese mineral, Mn2+
8 Si6 O15 (OH)10 . Kirk
b. An erroneous name for danburite.


ben

a. Scot. Inward; toward the workings; the workman's right to enter the
pit.
b. The live or productive part of a lode. Arkell
c. A mountain peak; a word occurring chiefly in the names of many of the
highest summits of the mountains of Scotland, as Ben Nevis.




bench

a. A terrace on the side of a river or lake having at one time formed its
bank. See also:bench gravel
b. In an underground mine, a long horizontal face or ledge of ore in a
stope or working place. CTD
c. A layer of coal; either a coal seam separated from nearby seams by an
intervening noncoaly bed, or one of several layers within a coal seam that
may be mined separately from the others. AGI
d. One of two or more divisions of a coal seam, separated by slate, etc.,
or simply separated by the process of cutting the coal, one bench or layer
being cut before the adjacent one.
e. The horizontal step or floor along which coal, ore, stone, or
overburden is worked or quarried. See also:benching; opencast.
Nelson
f. A stratum of coal forming a portion of the seam; also, a flat place on
a hillside indicating the outcrop of a coal seam. BCI g. In tunnel excavation, where a top heading is driven, the bench is the
mass of rock left, extending from about the spring line to the bottom of
the tunnel. Stauffer
h. A part of the face of a large excavation that is advanced not as part
of the round but as a separate operation. BS, 12
i. A ledge that, in open-pit mine and quarries, forms a single level of
operation above which minerals or waste materials are excavated from a
contiguous bank or bench face. The mineral or waste is removed in
successive layers, each of which is a bench, several of which may be in
operation simultaneously in different parts of, and at different
elevations in, an open-pit mine or quarry. CF:berm
j. See:siege




bench-and-bench

Ark. That plan of mining coal in a room that requires the blasting of the
two benches of coal alternately, each a little beyond the other.
Syn:bench working




bench blasting

A mining system used either underground or in surface pits whereby a thick
ore or waste zone is removed by blasting a series of successive horizontal
layers called benches.




bench claim

A placer claim located on a bench above the present level of a stream.
Hess




bench coal

A coal seam cut in benches or layers. Tomkeieff




bench cut

a. In vertical shaft sinking, blasting of drill holes so as to keep one
end of a rectangular opening deep (leading), thus facilitating drainage
and removal of blasted rock. Pryor, 3
b. Benches in tunnel driving are often drilled from the top with
jackhammers. The vertical shotholes are generally spaced 4 ft (1.2 m)
apart in both directions, fired by electric delay detonators, one row at a
time. When bench shotholes are drilled horizontally with the drifter
drills mounted on a bar, the charges are fired in rotation, starting from
the upper center. In some cases, a bench may be drilled both vertically
and horizontally, particularly where the benches are exceptionally high or
when the headroom above the bench is inadequate for handling drill steels
long enough to bottom the shotholes to grade. The lifters are drilled by
machines mounted on a bar across the bottom of the tunnel, in which case
the upper vertical holes will all be fired before the horizontal charges.
Hammond




bench diggings

River placers not subject to overflows.




benched foundation

Foundation excavated on a sloping stratum of rock, which is cut in steps
so that it cannot slide when under load. Syn:stepped foundation
Hammond




benches

A name applied to ledges of all kinds of rock that are shaped like steps
or terraces. They may be developed either naturally in the ordinary
processes of land degradation, faulting, and the like; or by artificial
excavation in mines and quarries.




bench face

See:bank




bench flume

A conduit on a bench, cut on sloping ground. Seelye, 1




bench gravel

A term applied in Alaska and the Yukon Territory to gravel beds on the
side of a valley above the present stream bottom, which represent part of
the stream bed when it was at a higher level. See also:bench;
bench placer. AGI




bench height

The vertical distance from the top of a bench to the floor or to the top
of the next lower bench.




benching

a. A method of working small quarries or opencast pits in steps or
benches, in which rows of blasting holes are drilled parallel to the free
face. The benching method has certain dangers since the quarrymen must
work on ledges at some height. It is possible to work benches up to 30 ft
(9.1 m) high using tripod or wagon drills. See also:bottom benching;
top benching. Nelson
b. The breaking up of a bottom layer of coal with steel wedges in cases
where holing is done above the floor. Nelson
c. Ches. The lower portion of the rock salt bed worked in one operation.
Fay
d. See:bench




benching iron

An item of surveying equipment, comprising a triangular steel plate with
pointed studs at the corners. These studs are driven into the ground in
the desired position. The plate is used either as a temporary bench mark
or as a change point in running a line of levels. Hammond




bench mark

a. A relatively permanent metal tablet or other mark firmly embedded in a
fixed and enduring natural or artificial object, indicating a precisely
determined elevation above or below a standard datum (usually sea level);
it bears identifying information and is used as a reference in topographic
surveys and tidal observations. It is often an embossed and stamped disk
of bronze or aluminum alloy, about 3.75 in (9.5 cm) in diameter, with an
attached shank about 3 in (7.6 cm) in length, and may be cemented in
natural bedrock, in a massive concrete post set flush with the ground, or
in the masonry of a substantial building. Abbrev: BM. AGI
b. A well-defined, permanently fixed point in space, used as a reference
from which measurements of any sort (such as of elevation) may be made.
AGI




bench of timbers

A term used to describe the header when it is complete with legs.
Syn:set




bench placer

A bench gravel that is mined as a placer. Syn:bench gravel;
river-bar placer; terrace placer. AGI




bench scrap

The scrap mica resulting from rifting and trimming hand-cobbed mica.
Skow




bench slope

See:bank slope


bench working

The system of working one or more seams or beds of mineral by open working
or stripping in stages or steps. Syn:bench-and-bench




benchy

Forming frequent benches; said of a lode. Standard, 2




Bendelari jig

A jig fitted with a flexible rubber diaphragm that is worked by an
eccentric motion, thus producing a jigging cycle (pulsion suction).
See also:jig




bending stress

The stress produced in the outer fibers of a rope by bending over a sheave
or drum. Zern




bend pulley

An idler pulley that is used solely for the purpose of changing the
direction of travel of the belt other than at the terminals of the
conveyor. NEMA, 2




bend radius

The inside radius of a bent section. ASM, 1




bends

Caisson disease, brought on by too sudden return to normal pressure after
working in a pressurized shaft or tunnel. Pryor, 3




bend shaft

A shaft that supports a bend wheel or pulley.




bend tangent

A tangent point where a bending arc ceases or changes. ASM, 1




bend test

A test for determining relative ductility of metal that is to be formed,
usually sheet, strip, plate, or wire, and for determining soundness and
toughness of metal. The specimen is usually bent over a specified diameter
through a specified angle for a specified number of cycles. ASM, 1




bend wheel

A wheel used to interrupt and change the normal path of travel of the
conveying or driving medium. Most generally used to effect a change in
direction of conveyor travel from inclined to horizontal or a similar
change.




beneficiate

To improve the grade by removing associated impurities; to upgrade.




beneficiation

a. The dressing or processing of coal or ores for the purpose of (1)
regulating the size of a desired product, (2) removing unwanted
constituents, and (3) improving the quality, purity, or assay grade of a
desired product.
b. Concentration or other preparation of coal or ores for smelting by
drying, flotation, or magnetic separation.
c. Improvement of the grade of coal or ores by milling, flotation,
sintering, gravity concentration, or other processes.




Bengal amethyst

An archaic trade name for purple sapphire.




benitoite

A hexagonal mineral, 2[BaTiSi3 O9 ] ; occurs in double
pyramids; colorless, white, or blue, resembling sapphire; in veins in
serpentine schist.




benjaminite

A monoclinic mineral, (Ag,Cu)3 (Bi,Pb)7 S12 .




benstonite

A trigonal mineral, (Ba,Sr)6 (Ca,Mn)6 Mg(CO3 ) (sub
13) ; shows flat, simple rhombohedral crystals and cleavage; fluoresces
yellow or red; in veins with calcite.




bent

a. In tunnel timbering, two posts and a roof timber. Nichols, 1
b. A transverse structure consisting of legs, bracing, and feet used for
the purpose of supporting a gallery or conveyor frame at a fixed
elevation.




Benthic Division

A primary division of the sea that includes all of the ocean floor. The
Benthic Division is subdivided into the Littoral System (the ocean floor
lying in water depths ranging from the high watermark to a depth of 200 m
or the edge of the continental shelf), and the Deep-Sea System (ocean
floor lying in water deeper than 200 m). The systems are further
subdivided into the Eulittoral Zone (0 to 50 m), Sublittoral Zone (50 to
200 m), Archibenthic Zone (200 to 1,000 m), and the Abyssal-Benthic Zone
(1,000 m and greater). Hy




benthonic

a. Refers to the bottom of a body of standing water. AGI
b. Pertaining to benthos; also, said of that environment. Syn:demersal
AGI




benthos

All plants and animals living on the ocean bottom. Hy


bentonite

A montmorillonite-type clay formed by the alteration of volcanic ash. It
varies in composition and is usually highly colloidal and plastic.
Swelling bentonite is so named because of its capacity to absorb large
amounts of water accompanied by an enormous increase in volume. Occurs in
thin deposits in the Cretaceous and Tertiary rocks of the Western United
States. It is used for making refractory linings, water softening,
decolorizing oils, thickening drilling muds, and preparing fine grouting
fluids. As a mud flush, bentonite is used at a concentration of about 3
lb/ft3 (48.1 kg/m3 ) of water. Syn:Denver mud;
volcanic clay. See also:clay




bentonitic clay

Bentonite.




bent sieve

A stationary screen constructed in the form of an arc of a circle and
arranged as a chute over which the clean coal from a cyclone washer passes
to the orthodox rinsing screen. In the United States, the bent screen is
used in magnetite recovery from cyclone washers. Nelson




benzenol

See:phenol




benzol indicator

A portable instrument designed specif. for measuring low concentrations of
benzol, which are potentially dangerous to the health of personnel.
Best, 1




beraunite

A monoclinic mineral, Fe2+ Fe3+5 (PO4 )
4 (OH)5 .4H2 O ; a secondary mineral in iron deposits;
an alteration product of primary phosphates in pegmatites.




berdan

A circular, revolving, inclined iron pan in which concentrates are ground
with mercury and water by an iron ball. Gordon




Berek compensator

In polarized-light microscopy, an optical device of variable compensation
for analysis of birefringence. CF:accessory plate




bergalite

A pitchy black dike rock containing small phenocrysts of haueyne, apatite,
perovskite, melilite, and magnetite in a groundmass of the same minerals
with nepheline, biotite, and brown interstitial glass; from Kaiserstuhl,
Oberbergen, Baden, Germany. Syn:bergalith




bergalith

See:bergalite




bergbutter

Various salts, commonly halotrichite. Hey, 1




bergenite

Occurs naturally at Bergen an der Trieb, Saxony, with other uranium
minerals; named from locality, the older name being rejected as implying a
barian phosphuranylite rather than the barium analogue. Syn. for
barium-phosphuranylite. Hey, 2




Berglof process

A method of direct reduction of iron ore. The reduction of the ore was
carried out in interchangeable containers. The ore was heated to the
reduction temperature in one container, and then this container was moved
into the reducing zone. Osborne




berkeleyite

See:lazulite




berkelium

The element having the atomic number 97, the discovery of which was
announced by Thompson, Ghiorso, and Seaborg in 1950. They produced an
isotope of 4.5 h half-life, berkelium 243, by helium ion bombardment of
americium 241. Symbol, Bk; valences, 3 and 4; and the mass number of the
most stable isotope, 249. Handbook of Chemistry and Physics, 2




Berlin blue

In optical mineralogy, an anomalous interference color of the first order;
e.g., some epidotes.




Berlin iron

A soft iron containing phosphorus, which makes very fine smooth castings
and is used for ornaments and jewelry. Standard, 2




berm

a. A horizontal shelf or ledge built into the embankment or sloping wall
of an open pit or quarry to break the continuity of an otherwise long
slope and to strengthen its stability or to catch and arrest slide
material. A berm may be used as a haulage road or serve as a bench above
which material is excavated from a bank or bench face. CF:bench
b. The space left between the upper edge of a cut and the toe of an
embankment. Seelye, 1
c. An artificial ridge of earth. Nichols, 2
d. Terraces that originate from the interruption of an erosion cycle with
rejuvenation of a stream in the mature stage of its development and
renewed dissection, leaving remnants of the earlier valley floor above
flood level. AGI
e. A nearly horizontal portion of the beach or backshore formed by the
deposit of material by wave action. Some beaches have no berms; others
have one or several. See also:bank height




bermanite

A monoclinic mineral, Mn2+ Mn3+2 (PO4 )
2 (OH)2 .4H2 O ; in pegmatites.




berm interval

Vertical distance from crest of berm to its underlying toe, as in a bank
or bench.




bernardinite

Originally described by Stillman as fossil resin, but later shown by
Stanley-Brown to be a fungus impregnated by resinous material.
Tomkeieff


bernstein

a. A fossil resin found in and in association with lignite beds of Eocene
age. Commonly occurring in many European localities, and is esp. abundant
in areas bordering the Baltic coast. See also:amber
b. German name for amber. Tomkeieff




berthierine

A monoclinic mineral, (Fe2+ ,Fe3+ ,Mg)2-2D3
(Si,Al)2 O5 (OH)4 of the kaolinite-serpentine group;
dark steel-gray; in low-temperature vein deposits.
Syn:martourite




berthonite

A discredited name for bournonite.




bertrandite

An orthorhombic mineral, 4[Be4 Si2 O7 (OH)2 ];
colorless to clear pale yellow and shows heart-shaped twins; in
pegmatites; a source of beryllium. See also:beryllium disilicate




Bertrand lens

A removable lens in the tube of a polarized-light microscope used to
converge light to form an interference figure.




Bertrand process

A heavy-fluid coal cleaning process that utilizes a calcium chloride
solution as separating medium and is applicable only to deslimed feed. It
differs from the Lessing process in that the raw coal is introduced into
the system countercurrent fashion, from water to separating solution, the
purified coal and the waste being withdrawn in a similarly countercurrent
fashion. Coal containing less than 1% ash is said to be obtained by this
process. Gaudin, 1




beryl

A hexagonal mineral, Be3 Al2 Si6 O18 ; green,
blue-green, and other pale tints; in granite pegmatites, mica schists, and
an accessory mineral in felsic igneous rocks; the chief source of
beryllium. Transparent and colored gem varieties include emerald,
aquamarine, morganite, heliodor, golden beryl, bixbite, and vorobievite.




beryllides

A group of intermetallic compounds of potential interest as special
ceramics. Cell dimensions and types of structure have been reported for
the beryllides of titanium, vanadium, chromium, zirconium, niobium,
molybdenum, hafnium, and tantalum. Dodd




berylliosis

An occupational disease caused by the inhalation of fumes liberated during
the reduction of beryllium. Beryllium is thought to play the principal
role, aggravated by fluorine, and to affect all organs, particularly the
larger protective glands, rather than the respiratory apparatus alone.
Hess




beryllite

A hydrous silicate of beryllium, Be3 SiO4 (OH)2 .H
2 O , as an alteration product of epididymite. Spencer, 5




beryllium

An element belonging to the alkaline earth metals. Symbol, Be. Beryl and
bertrandite are the most important commercial sources of the element and
its compounds. Aquamarine and emerald are the precious forms of beryl.
Used in nonsparking tools, high-speed aircraft, missiles, spacecraft,
communications satellites, and X-ray lithography for microminiature
integrated circuits, as well as in nuclear reactors and computers.
Beryllium and its salts are toxic.




beryllium aluminate

BeAl2 O4 ; mol wt, 126.97; orthorhombic; sp gr, 3.76; source
of beryllium. Syn:chrysoberyl




beryllium carbide

Be2 C ; decomposes above 2,950 degrees C. Used as a moderator in
nuclear application. Molecular weight, 30.04; yellow; hexagonal; and sp
gr, 1.90 at 15 degrees C. Lee; Bennett




beryllium disilicate

Be4 Si2 O7 (OH)2 ; mol wt, 238.23;
orthorhombic; sp gr, 2.6. Syn:bertrandite




beryllium nitride

Be3 N2 ; molecular weight, 55.05; colorless; isometric; and
melting point, 2,200 + or - 100 degrees C. Bennett




beryllium oxide

A white powder; hexagonal; BeO. Used in the preparation of beryllium
compounds and in ceramics and refractories. Melting point, 2,570 degrees
C; and sp gr, 3.02. Bodies high in BeO have extremely high thermal
conductivity (in the range of metals) and also possess high mechanical
strength. Used in nuclear reactors because of its refractoriness, high
thermal conductivity, and ability to act as a moderator for fast neutrons,
reducing them to thermal speeds. Beryllia ceramics are used for electronic
components and for crucibles for melting uranium and thorium.
Syn:bromellite




beryllonite

A monoclinic mineral, NaBePO4 ; colorless or yellow; forms
transparent, topazlike pseudo-orthorhombic crystals.




beryloid

In crystallography, the dihexagonal bipyramid, common in crystals of
beryl.




beryloscope

See:emerald glass




beryl preferential stain process

A quick, simple method for determining the amount of beryl in a mineral
sample. The samples are placed in a hot solution of sodium hydroxide,
which etches the beryl grains in the sample; they then are stained an
intense blue with another reagent to enable counting under a microscope.




berzelianite

An isometric mineral, Cu2 Se ; silver-white in fresh break; sp gr,
6.7. ; dimorphous with bellidoite.


berzeliite

An isometric mineral, (Ca,Na)3 (Mg,Mn)2 (AsO4 ) (sub
3) ; commonly massive; bright yellow to orange-yellow.
Syn:pyrrhoarsenite




Bessemer

Any product of the Bessemer process, such as Bessemer steel, iron, etc.;
named from Henry Bessemer, who patented the process in 1855; used also
attributively as Bessemer converter, flame, or method. Standard, 2




Bessemer afterblow

In the basic Bessemer process of steelmaking, the continuation of the
blowing cycle after the oxidation of the silicon, manganese, and carbon
content of the charge is complete, and during which the phosphorus and
sulfur contents of the charge are reduced. Henderson




Bessemer blow

In the Bessemer process of steelmaking, the period of the blowing cycle
during which the oxidation of the silicon, manganese, and carbon content
of the charge takes place. Henderson




Bessemer converter

A pear-shaped steel shell lined with a refractory material containing a
number of holes or ports in the bottom or side through which air is blown
through the molten pig iron charge. The converter is mounted on trunnions
about which it may be tilted to charge or tap. Molten pig iron is charged
into the converter, and air is blown through the molten metal to oxidize
the impurities, thus making steel. Henderson




Bessemer iron ore

See:Bessemer ore




Bessemer matte

In the extraction of copper from sulfide ores, the liquid that remains in
the converter at the end of the blow. It is essentially molten nickel
sulfide or a solution of copper and nickel sulfides. Newton, 1




Bessemer ore

An iron ore containing very little phosphorus (generally less than
0.045%). Named for suitability in the Bessemer process of steelmaking.
Syn:Bessemer iron ore




Bessemer pig iron

Pig iron with sufficiently low phosphorus (0.100% maximum) to be suitable
for use in the Bessemer process. ASM, 1




Bessemer process

A method, historically important but no longer in use, in which molten pig
iron is charged in a Bessemer converter and air is blown through the
molten metal to oxidize the impurities, thus making steel. This process is
no longer in use.




beta

In crystallography, the angle between the a and c axes. CF:alpha;
gamma.




beta chalcocite

See:chalcocite




betafite

An isometric mineral, (Ca,Na,U)2 (Ti,Nb,Ta)2 O6 (OH);
pyrochlore group; forms a series with pyrochlore; name assigned to
members of the series having uranium greater than 15%; radioactive; in
granitic pegmatites. CF:uranpyrochlore




beta particle

An elementary particle emitted from a nucleus during radioactive decay. It
has a single electrical charge and a mass equal to 1/1837 that of a
proton. A negatively charged beta particle is physically identical to an
electron. If the beta particle is positively charged, it is called a
positron. Lyman




beta quartz

Quartz formed at a temperature between 573 degrees C and 870 degrees C.
The commonest examples are the bipyramidal quartz crystals found as
phenocrysts in quartz porphyries. Hess




beta ray

A ray of electrons emitted during the spontaneous disintegration of
certain atomic nuclei. ASM, 1




beta tin

Metallic tin in its common, massive form. Bennett




betatron

A doughnut-shaped accelerator in which electrons are accelerated by a
changing magnetic field. Lyman




beta zinc sulfide

Colorless when pure; isometric; ZnS; mol wt, 97.43; sp gr, 4.102 at 25
degrees C, and ranges from 3.90 to 4.11; Mohs hardness, 3.5 to 4.0;
luster, resinous to adamantine; transformation temperature to alpha zinc
sulfide, 1,020+ or -5 degrees C; sublimes at 1,180 degrees C or 1,185
degrees C; melting point, 1,850 degrees C (at 150 atm or 15.2 MPa);
insoluble in water; and very soluble in acids. Occurs as the mineral
sphalerite, which is nearly colorless, white, yellow, red, green, brown,
and black; has perfect dodecahedral cleavage; and is soluble in
hydrochloric acid. Sphalerite is the principal ore of zinc, a source of
cadmium, and a source of sulfur for manufacturing sulfur dioxide, sulfuric
acid, and other sulfur compounds. Also called sphalerite; zinc blende;
zincblende; blende; black jack. See also:sphalerite; zinc sulfide.
CF:alpha zinc sulfide
CCD, 2; Handbook of Chemistry and Physics, 2; Dana, 2




betechtinit

See:betekhtinite




betekhtinite

Orthorhombic needles, Cu10 (Fe,Pb)S6 , in ores from
Mansfeld, Germany. Syn:betechtinit


Bethell's process

A process for creosoting timber (such as track sleepers) to extend its
useful life. The timber is first dried, then placed in a cylinder and
subjected to partial vacuum, and finally impregnated with creosote under
pressure. See also:open-tank method; timber preservation.
Nelson




between-laboratory tolerance

The maximum acceptable difference between the means of two determinations
carried out by two different laboratories on representative samples taken
from the same bulk sample after the last stage of the reduction process.
BS, 1




beudantite

a. A trigonal mineral, PbFe3+3 (AsO4 )(SO4
)(OH)6 ; crystallizes in green to black rhombohedra.
b. A mineral group.




bevel cut

Any style of cutting with a large table joined to the girdle by one, or
possibly two, bevels and a pavilion that may be step cut, brilliant cut,
or any style. Used mostly for opaque stones and intaglios. Bevel-cut
shapes include round, square, rectangular, oblong, oval, pendeloque,
navette, heart, diamond, horseshoe, shield, pentagon, and hexagonal
shapes. The style is used predominantly for less valuable gems.
Syn:table cut




bevel gear

a. A cone-shaped gear encircling the drive rod in a diamond-drill swivel
head, which meshes with a matching gear attached to the drive shaft from
the drill motor. By means of these gears, the drill-string equipment can
be made to rotate. Syn:miter gear
b. Any gear, the teeth of which are inclined to the shaft axis of the
gear. Long
c. A gearwheel that transmits power between two shafts that meet at an
angle. If at a right angle and the wheel is of the same size, it is called
a miter gear. Crispin




beyerite

A tetragonal mineral, (Ca,Pb)Bi2 (CO3 )2 O2 ;
forms minute tetragonal crystals and earthy masses; a secondary bismuth
mineral.




B.H. bit

a. A noncoring or blasthole bit. Long
b. A CDDA standard-size noncoring bit having a set outside diameter of 1
in (2.54 cm). Normally referred to as a 1-in B.H. bit. Long




B-horizon

The layer of a soil profile in which material leached from the overlying
A-horizon is accumulated. Syn:zone of accumulation;
zone of illuviation. See also:A-horizon




biard

See:bearers




biat

Eng. A timber stay or beam in a shaft. See also:bearer
byat.




biaxial

The optical character of crystals belonging to the orthorhombic,
monoclinic, and triclinic systems, which exhibit double refraction, but
have two directions of single refraction and isotropy, i.e., two optic
axes. CF:uniaxial




biaxial stone

A mineral that has crystallized in the orthorhombic, monoclinic, or
triclinic system and hence has two optic axes. CF:uniaxial stone




bicable

An aerial ropeway using stationary track ropes along which carriers are
hauled by an endless haulage rope. See also:aerial ropeway
Nelson




bicylindroconical drum

A winding drum with a cylindrical middle portion and two conical outer
portions; used sometimes where the weight of the winding rope is large
compared with the coal or mineral load. The heavily loaded upgoing rope
winds on the small diameter, while the downgoing rope winds off the large
diameter. The effect is to compensate for the heavy torques due to rope
unbalance and acceleration. See also:cylindroconical drum;
winding drum. Nelson




bieberite

A monoclinic mineral, CoSO4 .7H2 O ; melanterite group;
flesh-red to rose-red; esp. in crusts and stalactites.
Syn:cobalt vitriol




bifurcating feeder

One that separates objects moving in a single lane and delivers them to
two lanes of movement.




Big Coal D

Nongelatinous permissible explosive; used in coal mining. Bennett




bigging

N. of Eng. A built-up pillar of stone or other debris in a working place
or heading to support the roof; e.g., "bigging the gob" means building a
pack in a worked-out place.




big-stone bit

Bits set with diamonds as large or larger than eight stones per carat in
size. Long




bikitaite

A monoclinic and triclinic mineral, LiAlSi2 O6 .H2 O;
may be in zeolite group; colorless or white; in granular aggregates with
eucryptite in lithia pegmatites.




bilateral transducer

A transducer capable of transmission in either direction between its
terminations. Syn:reversible transducer


Bilharz table

A side-bump table having a surface made of a plane, endless, traveling
belt. The Corning, Luhrig, and Stein tables are similar. Liddell




bilinite

A monoclinic mineral, Fe2+ Fe3+2 (SO4 )
4 .22H2 O ; hallotrichite group; white to yellowish; in
radially fibrous masses.




billy

Aust. A name used in the Clermont district of Queensland for a bed of
quartzite that caps the coal measures.




billy coal

Staff. Miners' term for a thin, unworkable coal seam occurring above or
below a workable seam. Tomkeieff




bimagmatic

Generic term for porphyritic rocks in which the minerals occur in two
generations. AGI




bin

A container for storing material.




binary alloy

An alloy containing two component elements. ASM, 1




binary cycle

A cycle in which two different media are employed, one superimposed on and
augmenting the cycle of the other. Strock, 2




binary explosive

An explosive based on two ingredients, such as nitromethane and ammonium
nitrate, which are shipped and stored separately and mixed at the blast
site to form an explosive mixture.




binary granite

Two-mica granite.




binary system

A chemical system containing two components, e.g., the MgO-SiO2
system. AGI




bind

a. Shale or mudstone occurring in coal measures. Obsolete. BS, 11
b. To prevent normal operation of drill-string equipment in a borehole,
such as by constriction or friction created by swelling or caving ground,
settlement or balling of cuttings, an obstruction, or an offset or crooked
hole, or as the result of insufficient clearance cut by use of undergage
bits or reaming shells. Long
c. To cause to cohere; to give consistency to by means of an agent, such
as by drilling mud in a loose, sandy, or fragmented formation.
Long
d. A British coal miner's term for any fine-grained, well-laminated rock
(such as shale, clay, or mudstone, but not sandstone) associated with
coal. See also:blaes




binder

a. A substance used to produce cohesion in loose aggregate, as the crushed
stones in a macadam road.
b. A material added to coal or iron ore during the process of briquetting
or pelletizing to facilitate adhesion between the particles.
c. Corn. Beds of grit in shale, slate, or clay.
d. Streak of impurity in a coal seam, usually difficult to remove.
e. The material that produces or promotes consolidation in loosely
aggregated sediments; e.g., a mineral cement that is precipitated in the
pore spaces between grains and that holds them together, or a primary clay
matrix that fills the interstices between grains. AGI
f. Soil binder. AGI
g. A term used in Ireland for a bed of sand in shale, slate, or clay.
AGI
h. A coal miner's term used in Pembrokeshire, England, for shale.
AGI




binderless briquetting

The briquetting of coal by the application of pressure without the
addition of a binder. BS, 5




bindheimite

An isometric mineral, Pb2 Sb2 O6 (O,OH) ; stibiconite
group; yellow to reddish-brown; in the oxidation zone of lead-antimony ore
deposits.




binding bolt

See:anchor bolt




bin feeder

A worker who rods or bars ore that sticks as it passes through the bin
door. Fay




bing

To put coal in wagons or in stacks at the surface. Fay




bin gate

A device for complete shutoff or control of gravity-impelled flow of
materials from a bin, bunker, hopper, or other container.
Syn:bucket gate; bunker gate. See also:regulating gate




Bingham model

One of many rheological models of material behavior. Rheology is the study
of change in form and the flow of matter, embracing elasticity, viscosity,
and plasticity. A Bingham material is elastic until the yield point is
reached; flow occurs beyond the yield point. SME, 1




bing hole

Derb. A hole or chute through which ore is thrown.


bing ore

The purest lead ore and with the largest crystals of galena. Hess




bing place

Derb. The place where ore is stored for smelting.




binnite

A silver-bearing variety of tennantite.




bioassay

A determination of the concentration of a substance in biological fluids
and tissue by analysis of urine, feces, blood, bone, tissue, etc.
ANSI




biochemical deposit

A precipitated deposit resulting directly or indirectly from vital
activities of an organism, such as bacterial iron ore or coralline
limestone.




biochemical prospecting

a. See:biogeochemical prospecting
b. Prospecting by means of vegetation. The root systems of trees are
actually powerful sampling mechanisms that represent samples of solutions
from a large volume of earth. Much of the mineral content from these
solutions is found in the leaves. Analysis of leaves may serve as a guide
to prospectors. Lewis




bioclastic

Said of rocks consisting of fragmental organic remains.




biogenic

Said of a rock resulting from the physiological activities of organisms,
e.g., a coral reef.




biogeochemical anomaly

An area where the vegetation contains an abnormally high concentration of
metals. Hawkes, 2




biogeochemical prospecting

Geochemical exploration based on the chemical analysis of systematically
sampled plants in a region, to detect biological concentrations of
elements that might reflect hidden orebodies. The trace-element content of
one or more plant organs is most often measured.
Syn:biochemical prospecting
AGI




biogeochemistry

A branch of geochemistry that deals with the effects of life processes on
the distribution and fixation of chemical elements in the biosphere.
AGI




bioherm

A moundlike or circumscribed mass of rock built up by sedentary organisms
such as corals, mollusks, and algae. CF:biostrome




bioleaching

The catalytic action of bacteria, such as Thiobacillus ferroxidans and
Thiobacillus thiooxidans to accelerate chemical oxidation reactions by as
much as 106 times those of chemical reactions alone; esp. useful
in leaching copper and uranium systems. SME, 1




biolite

a. A group name for minerals formed by biologic action. AGI
b. See:biolith
c. An old term for a concretion formed through the action of living
organisms. AGI




biolith

A rock of organic origin; a biogenic rock.




bioluminescence

The emission of visible light by living organisms. Hy




biomechanical deposit

A deposit due to the detrital accumulation of organic material, as in the
cases of limestones and coal. AGI




bionomics

See:ecology




biopelite

See:black shale




biophile

a. An element that is required by or found in the bodies of living
organisms. The list of such elements includes carbon, hydrogen, oxygen,
nitrogen, phosphorus, sulfur, chlorine, iodine, bromine, calcium,
magnesium, potassium, sodium, vanadium, iron, manganese, and copper. All
may belong also to the chalcophile or lithophile groups. Hess
b. Said of those elements that are the most typical in organisms and
organic material. AGI
c. Said of those elements that are concentrated in and by living plants
and animals. AGI




bioreactor

A tank equipped for temperature, pH, and reagent control used to employ
bacteria to oxidize or reduce ores of gold and other metals and render
them amenable for metal extraction by leaching.


biosphere

a. All the area occupied or favorable for occupation by living organisms.
It includes parts of the lithosphere, hydrosphere, and atmosphere.
AGI
b. All living organisms of the Earth and its atmosphere. AGI




biostrome

A bedded, blanketlike mass of rock composed mainly of the remains of
sedentary organisms; an organic layer, such as a bed of shells or corals,
or even a coal seam. CF:bioherm




biotite

a. A monoclinic mineral, K2 Mg6 (Si6 Al2 O
20 )(OH,F)2 ; mica group, with Fe2+ replacing Mg and
Fe3+ replacing Al; in masses with perfect basal cleavage; dark
brown, dark green, black; a common rock-forming mineral in crystalline
rocks, either as an original crystal in igneous rocks or as a metamorphic
product in gneisses and schists; a detrital constituent of sedimentary
rocks.
b. A general term to designate all ferromagnesian micas. Syn:black mica;
dark mica; magnesia mica. See also:iron mica




biotite gneiss

A gneiss in which biotite is the prominent dark mineral.




biotitite

A jet black igneous rock consisting essentially of biotite. Near Libby,
MT, such a rock has been altered to vermiculite by hot waters.
Johannsen




Biot number

The heat-transfer ratio hr/k, where h is the heat-transfer coefficient, r
is the distance from the point or plane under consideration to the
surface, and k is the thermal conductivity. The Biot number is a useful
criterion in assessing thermal-shock resistance. Dodd




bipolar electrode

An electrode that is not mechanically connected to a power supply but is
placed in an electrolyte, between the anode and the cathode, such that the
part nearer the anode becomes cathodic and the part nearer the cathode
becomes anodic. Syn:intermediate electrode




bipyramid

A closed crystal form consisting of a positive and negative pyramid.
CF:pyramid




bird

A geophysical measuring device such as a magnetometer, plus the housing in
which it is towed behind an aircraft. AGI




bird's-eye

a. Mixed screened anthracite passing a 1/2-in (12.7-mm) screen, but
retained on a 1/8-in (3.2-mm) screen. May be subdivided into buckwheat,
rice, and barley. See also:anthracite coal sizes; barley;
bird's-eye coal. CTD
b. Eng. Applied to various rocks with small spots, in some places to a
concretionary slate, and in Guernsey to a spotted variety of diorite or
gabbro. Arkell




bird's-eye coal

Sometimes applied to anthracite coal when very small fractures are
numerous and freshly broken surfaces display rounded or oval eyelike
forms, many of which have convex surfaces.
See also:anthracite coal sizes; bird's-eye. AGI




bird's-eye limestone

A very fine-grained limestone containing spots or tubes of crystalline
calcite.




bird's-eye porphyry

A name given by prospectors and miners to a fine-grained igneous rock
having small phenocrysts, particularly if they are quartz, from a fancied
resemblance to birds' eyes. Hess




bird's-eye slate

A quarryman's term for slate containing abundant deformed or squeezed
concretions. Holmes, 2




Bird solid-bowl centrifuge

A fine-coal dewatering machine that consists of a tank or truncated
conical shell, which is revolved at the desired speed by means of a drive
sheave. A screw conveyor rotates inside the cone or bowl at a slightly
lower speed in the same direction of rotation. The feed entrance, in the
center of the large end of the truncated cone, is high enough to allow
formation of a pool of slurry. Adjustable effluent-discharge parts are so
located in the large end of the bowl that the level of liquid is
maintained at the desired height. The solids are steadily moved forward by
the screw conveyor as fast as they are deposited, being carried above the
level of the pool for an interval before leaving the bowl. Discharge of
both solids and effluent is continuous.




birefracting

See:birefringent




birefractive

See:birefringent




birefringence

a. The numerical difference between the refractive indices of a mineral.
This difference results in a display of interference colors when thin
sections or small fragments of anisotropic minerals are viewed between
crossed polars. Isometric minerals and amorphous materials are isotropic
and have the same refractive index in every direction; they have no
birefringence and show no interference colors. See also:colors
b. The property of anisotropic crystals to split a beam of light into two
polarized rays that traverse the crystal at different velocities as they
pass through it and produce characteristic optical effects that are
recognizable with the proper instruments or, in some cases (e.g.,
calcite), by the eye alone. Syn:double refraction
CF:transmitted light




birefringent

Said of a crystalline substance that displays birefringence; such
materials have more than one index of refraction. Syn:birefractive;
birefracting.




birne

See:boule




birnessite

A monoclinic mineral, Na4 Mn14 O27 .9H2 O ;
black or dark-brown, named for Birness, Scotland.


Birtley coal picker

An electric picker that distinguishes between good coal and slate by their
different electrical conductivities. It is said to be more accurate than
the human slate picker, who, when fatigued, may fail to remove all the
impure material. Mitchell




Birtley contraflow separator

A pneumatic table for dry cleaning coal. It consists of perforated deck
plates arranged in a series of lateral steps with a longitudinal
inclination. A centrifugal fan provides a constant upward blast of air
through the deck. The usual layering takes place, the refuse sinking to
the deck plates. The capacity of the table ranges from 6 st/h per foot
(17.8 t/h/m) of width for sizes 1-1/2 to 2 in (3.8 to 5.1 cm), down to 2
st/h/ft (5.9 t/h/m) for fines below 1/16 in. They are built in any width
up to a maximum of about 8 ft (2.4 m). Nelson




bischofite

A monoclinic mineral, MgCl2 .6H2 O .




biscuit

a. Unglazed ceramic ware that has been fired in a biscuit or bisque oven
or film.
b. A small cake of primary metal, such as uranium, made from uranium
tetrafluoride and magnesium in a bomb reduction. ASM, 1




bishop's stone

See:amethyst




bisilicate

In metallurgy, a slag with a silicate degree of 2. Newton, 2




bismite

A straw-yellow monoclinic mineral, Bi2 O3 ; earthy to
powdery; in oxidized parts of bismuth ores. Syn:bismuth ocher




bismoclite

A tetragonal mineral, BiOCl .




bismuth

A white crystalline, brittle metal with a pinkish tinge. Symbol, Bi. The
most important ores are bismuthinite or bismuth glance (Bi2 S (sub
3) ) and bismite (Bi2 O3 ). Also obtained as a byproduct in
refining lead, copper, tin, silver, and gold ores. Forms low-melting
alloys that are used in fire detection and extinguishing systems; used as
a catalyst for making acrylic fibers and as a carrier for fuel in atomic
reactors; extensively used in cosmetics and in medicine.
Handbook of Chemistry and Physics, 3




bismuth blende

See:eulytite




bismuth glance

See:bismuthinite




bismuth gold

A pinkish-white native alloy of bismuth and gold, approx. Au2 Bi ;
contains 65.5% gold. See:maldonite




bismuthine

See:bismuthinite




bismuthinite

An orthorhombic mineral, 4[Bi2 S3 ] ; metallic; lead-gray to
tin-white with an iridescent tarnish; commonly associated with other ore
minerals; a source of bismuth. Syn:bismuth glance; bismuthine.




bismuth ocher

See:bismite




bismuth selenide

Bi2 Se3 ; black; orthorhombic; and melting point, 706
degrees C. Of some interest for thermoelectric applications. Also called
bismuth triselenide. Lee




bismuth spar

See:bismutite




bismuth telluride

Bi2 Te2 S ; hexagonal rhombohedral; gray; and a
thermoelectric material. Because it loses its semiconducting properties
above 100 degrees C, it is of value chiefly in cooling devices. Also
called bismuth tritelluride. Syn:tetradymite




bismutite

A tetragonal mineral, Bi2 (CO3 )O2 ; earthy or
amorphous. Syn:bismuth spar




bismutotantalite

An orthorhombic mineral, Bi(Ta,Nb)O4 .




bisphenoid

In crystallography, a form apparently consisting of two sphenoids placed
together symmetrically. CF:disphenoid


bit

Any device that may be attached to, or is, an integral part of a drill
string and is used as a cutting tool to bore into or penetrate rock or
other materials by utilizing power applied to the bit percussively or by
rotation. See also:detachable bit; drag bit. Long




bit blank

A steel bit in which diamonds or other cutting media may be inset by hand
peening or attached by a mechanical process such as casting, sintering, or
brazing. Syn:bit shank; blank; blank bit; body; shank. Long




bit clearance

a. Technically, the difference between the outside diameter of a set bit
and the outside set diameter of the reaming shell. Loosely, the term is
used to denote the clearing action of a bit, which is a function of the
waterways and the mode in which the diamonds or other cutting media are
set in the cutting face of the bit, and also the difference between the
outside set diameter of a bit and the outside diameter of the bit shank.
Long
b. Incorrectly and loosely used as a syn. for diamond exposure.
See also:diamond exposure




bit contour

The configuration of the crown or cutting face of a bit as seen in cross
section. Long




bit core

The central, removable, and replaceable portion or pilot of a noncoring or
other type of bit. CF:core




bit count

See:diamond count




bit crown

See:crown




bit-crown metal

See:diamond matrix




bit die

See:bit mold




bit disc

A bit with two or more rolling discs that do the cutting. Used in rotary
drilling through certain formations. Porter




bit drag

A bit with serrated teeth used in rotary drilling. Hess




bit face

That part of the bit crown that comes in contact with the bottom of a
borehole. It does not include that part of the bit crown that contacts the
walls of the borehole. Long




bit feed

See:feed rate




bit life

The average number of feet of borehole a bit may be expected to drill in a
specific type of rock under normal operating or specified conditions.
Long




bit load

The weight or pressure applied to a bit in drilling operations, expressed
as the number of pounds or tons of weight applied. Syn:bit pressure;
bit weight; drilling pressure; drilling weight; drill pressure; load.
Long




bit matrix

See:diamond matrix




bit mold

A steel, carbon, or ceramic die in which the shape of a bit crown is
incised and provided with pips, grooves, or holes in which diamonds are
set and held by suction or an adhesive. Filling the die with a matrix
alloy by a casting or a powder metal-sintering process affixes the shank
to a diamond-inset bit crown having a shape conforming to that incised in
the die. Syn:bit die; crown die; crown mold. Long




bit performance

The achievement of a bit as gaged by the overall cost of using a specific
bit per a unit measure of borehole drilled, or by the total number of feet
of borehole drilled per bit. Long




bit pressure

See:bit load




bit reaming shell

Obsolete name for reaming shell. Long




bit ring

a. See:setting ring
b. Obsolete name for core bit. Long


bit shank

a. The threaded part of a bit. Long
b. Sometimes incorrectly used as a syn. for bit blank. Long




bitter lake

A salt lake whose waters contain in solution a high content of sodium
sulfate and lesser amounts of the carbonates and chlorides ordinarily
found in salt lakes; a lake whose water has a bitter taste. Examples
include Carson Lake, NV, and the Great Bitter Lake in Egypt. AGI




bittern

a. The bitter liquid remaining after seawater has been concentrated by
evaporation until most of the sodium chloride has crystallized out.
AGI
b. A natural solution, in an evaporite basin, that resembles a saltworks
liquor, esp. in its high magnesium content. AGI




bitter salt

See:epsomite




bitter spar

a. A pure, crystalline dolomite that consists of 1 part or equivalent of
calcium carbonate and 1 part of magnesium carbonate. Syn:pearl spar
Fay
b. See:dolomite




bit thrust

The hydraulic pressure applied to a drill bit when drilling, as shown in
pounds per square inch by the pressure gages on the hydraulic-feed
cylinders of a diamond drill or the total pressure in pounds as calculated
by multiplying the recorded hydraulic pressure by the square-inch area of
the piston in the hydraulic-feed cylinder. Syn:drilling thrust
Long




bitumen

a. A general name for various solid and semisolid hydrocarbons. In 1912,
the term was used by the American Society for Testing and Materials to
include all those hydrocarbons that are soluble in carbon disulfide,
whether gases, easily mobile liquids, viscous liquids, or solids.
b. A generic term applied to natural flammable substances of variable
color, hardness, and volatility, composed principally of a mixture of
hydrocarbons substantially free from oxygenated bodies. Bitumens are
sometimes associated with mineral matter, the nonmineral constituents
being fusible and largely soluble in carbon disulfide, yielding
water-insoluble sulfonation products. Petroleums, asphalts, natural
mineral waxes, and asphaltites are all considered bitumens. AGI




bitumen cable

A cable notable for its resistance to moisture, but not suitable for high
temperatures. The wires are tinned to prevent reaction with the sulfur in
the bitumen. Outside the bitumen are layers of tape and jute, and one or
two layers of steel armoring; outside each layer of steel armoring are
layers of serving compound. Mason




bitumenite

Cannel coal from Torbane, Scotland. See also:torbanite
bituminite.




bitumen lapideum

An old name for mineral coal. Tomkeieff




bituminiferous

Yielding or containing bitumen. Standard, 2




Bituminite

High explosive used in mines. Bennett




bituminous

a. Containing bitumen.
b. Pertaining to bituminous coal. AGI
c. Having the odor of bitumen; often applied to minerals. d. Yielding volatile bituminous matter on heating (for example, bituminous
coal). AGI
e. Containing much organic, or at least carbonaceous, matter, mostly in
the form of the tarry hydrocarbons, which are usually described as
bitumen.




bituminous coal

a. Coal that ranks between subbituminous coal and anthracite and that
contains more than 14% volatile matter (on a dry, ash-free basis) and has
a calorific value of more than 11,500 Btu/lb (26.7 MJ/kg) (moist,
mineral-matter-free) or more than 10,500 Btu/lb (24.4 MJ/kg) if
agglomerating (ASTM). It is dark brown to black in color and burns with a
smoky flame. Bituminous coal is the most abundant rank of coal; much is
Carboniferous in age. CF:medium-volatile bituminous coal;
low volatile bituminous coal. Syn:soft coal
b. A coal that is high in carbonaceous matter, having between 15% and 50%
volatile matter. Soft coal. BCI
c. A general term descriptive of coal other than anthracite and
low-volatile coal on the one hand and lignite on the other. BS, 11
d. A coal with a relatively high proportion of gaseous constituents; dark
brown to black in color and burns with a smoky luminous flame. The coke
yield ranges from 50% to 90%. The term does not imply that bitumen or
mineral pitch is present. See also:coking coal




bituminous grout

A mixture of bituminous material and fine sand that will flow into place
without mechanical manipulation when heated. ASTM




bituminous limestone

A dark, dense limestone containing abundant organic matter, believed to
have accumulated under stagnant conditions and emitting a fetid odor when
freshly broken or vigorously rubbed; e.g., the Bone Spring Limestone of
Permian age in west Texas. Syn:stinkstone; anthraconite.
See also:swinestone




bituminous ores

Iron ores in which the gangue consists principally of coaly matter; e.g.,
black band ironstone. Osborne




bituminous rock

Natural or rock asphalt, but the term is sometimes used to describe a rock
in which the percentage of impregnation is comparatively low.
Nelson




bituminous shale

A shale containing bituminous material; coaly shale. CF:oil shale




bit wall

That portion of the bit between the crown and the shank of the bit.
Long




bit weight

a. Total weight, in carats, of the diamonds set in a diamond bit.
Long
b. Weight or load applied to a diamond bit during a drilling operation.
See also:bit load


bityite

A monoclinic mineral, CaLiAl2 (AlBeSi2 O10 )(OH) (sub
2) ; mica group; perfect basal cleavage.




bivalent

a. Having a valence of 2. Webster 3rd
b. Having two valences; e.g., cobalt has two forms, with valences of 2 and
3, respectively. Handbook of Chemistry and Physics, 2




bixbite

A red variety of beryl; in the Wah Wah and Topaz Mountains of Utah.




bixbyite

An isometric mineral, (Mn,Fe)2 O3 ; forms black cubes.
Formerly called partridgeite and sitaparite.




black alkali

An old term for an alkali soil whose sodium tends to disperse organic
matter and give a black color. CF:white alkali




black amber

A name given to jet that is found with amber. It becomes faintly electric
when rubbed. See also:jet; stantienite.




black andradite garnet

See:melanite




black ash

a. Any of various dark-colored products obtained in industrial processes.
Webster 3rd
b. A black mass containing chiefly soda in the form of sodium carbonate
and usually also sodium sulfide with some carbon, and produced esp. for
recovery of its soda content by concentrating and burning black liquor in
rotary furnaces. Webster 3rd




blackband

a. A dark, earthy variety of the mineral siderite, occurring mixed with
clay, sand, and considerable carbonaceous matter, and frequently
associated with coal. Syn:blackband ore
b. A thin layer (up to 10 cm in thickness) of blackband interbedded with
clays or shales in blackband ironstone. AGI
c. See:blackband ironstone




blackband ironstone

A dark variety of clay ironstone containing sufficient carbonaceous matter
(10% to 20%) to make it self-calcining (without the addition of extra
fuel). Syn:blackband




blackband ore

See:blackband




black bat

A piece of bituminous shale embedded in the rock immediately over the coal
measure and liable to fall of its own weight when the coal beneath it has
been removed. CF:kettle bottom




black body

As applied to heat radiation, this term signifies that the surface in
question emits radiant energy at each wavelength at the maximum rate
possible for the temperature of the surface and, at the same time, absorbs
all incident radiation. Only when a surface is a black body can its
temperature be measured accurately by means of an optical pyrometer.
Dodd




black box

A separate and self-contained electronic unit or element of an electronic
device which can be treated as a single package. NCB




black chalk

A bluish-black carbonaceous clay, shale, or slate, used as a pigment or
crayon. AGI




black cobalt

See:asbolan




black concentrate

The mixture of amalgam gold and magnetite obtained from behind the riffles
in a gold sluice. CTD




black copper

A name given to the impure metallic copper produced in blast furnaces
running on oxide ores or roasted sulfide material; an alloy of copper with
one or more other metals generally containing several percent of iron,
commonly lead, and many other impurities; also contains 1% to 3% sulfur.
See also:tenorite




black copper ore

An earthy, black, massive, or scaley form of copper oxide, CuO.
See also:melaconite; tenorite. Hess




black coral

An intense black to dark brown coral used in beads, bracelets, art
objects, etc.




black cotton

In India, soil from 6 to 10 ft (1.8 to 3.0 m) in thickness overlying the
coal measures, which, in dry weather, shrinks and produces mud cracks.


blackdamp

Generally applied to carbon dioxide. Strictly speaking, a mixture of
nitrogen and carbon dioxide. The average blackdamp contains 10% to 15%
carbon dioxide and 85% to 90% nitrogen. It is formed by mine fires and the
explosion of combustible gases in mines, and hence forms a part of the
afterdamp. An atmosphere depleted of oxygen rather than containing an
excess of carbon dioxide. Being heavier than air, it is always found in a
layer along the floor of a mine. It extinguishes light and suffocates its
victims. Hence, it is sometimes known as chokedamp. See also:afterdamp;
damp. Fay; Korson




black diamond

a. A variety of crystalline carbon, related to diamond, but showing no
crystal form. Highly prized as an abrasive because of its hardness. Occurs
only in Brazil. Syn:carbonado
b. A term frequently applied to coal.
c. A black gem diamond.
d. Dense black hematite that takes a polish like metal.




black flux

A reducing flux composed of powdered carbon and alkali-metal carbonate.
Webster 3rd




black garnet

See:andradite




black gold

a. A slang American term referring to crude oil.
b. Syn:Maldonite
c. Placer gold coated with a black or dark-brown substance (such as a film
of manganese oxide) so that the yellow color is not visible until the
coating is removed. AGI




black granite

A commercial term for crystalline rock that when polished is dark gray to
black. It may be a diabase, diorite, or gabbro. AGI




black gunpowder

A mixture of potassium nitrate (saltpeter), sulfur, and charcoal in
varying proportions. A typical composition is 70% to 75% saltpeter, 10% to
14% sulfur, and 14% to 16% charcoal. It is designated according to grain
size: mealed; superfine grain (FFG); fine grain (FG); large or coarse
grain (LG); large grain for rifles (RLG); and mammoth.
Syn:black powder




black hematite

See:psilomelane




black iron

Malleable iron, untinned; distinguished from tinned or white iron.
Standard, 2




black iron ore

See:magnetite




blackjack

a. A thin stratum of coal interbedded with layers of slate; a slaty coal
with a high ash content. AGI
b. A syn. of sphalerite, esp. a dark variety. See also:sphalerite
AGI




black lead

a. An obsolete name for graphite, still used in naming lead pencils, which
are really made of graphite. Syn:plumbago
b. Graphite, in impure crystalline form. Pryor, 3
c. Used for coating patterns and the faces of cast-iron chilling molds.
Crispin




blacklead ore

An early name for the black variety of cerussite. Fay




black light

a. A prospector's and miner's term for ultraviolet light, used in
exploration and evaluation to detect mineral fluorescence. AGI
b. An instrument, usually portable, that produces ultraviolet light for
this purpose. See also:lamp




black liquor

The alkaline spent liquor from the digesters in the manufacture of sulfate
or soda wood pulp.




black liquor recovery furnaces

Smelting or recovery furnaces in which evaporated black liquor is burned
to a molten chemical smelt.




blacklung

See:anthracosis




black magnetic rouge

A polishing material consisting of 99% Fe3 O4 .
See also:black rouge




black manganese

a. See:hausmannite
b. A term applied to dark-colored manganese minerals; e.g., pyrolusite,
hausmannite, and psilomelane.




black metal

A black shale associated with coal measures. AGI




black mica

See:biotite


black muck

Lanc. A dark-brown powdery substance, consisting of silica, alumina, and
iron; found in iron mines.




black mud

A mud formed in lagoons, sounds, or bays, in which there is poor
circulation or weak tides. The color is black because of iron sulfides and
organic matter. AGI




black ocher

See:wad; bog manganese.




black opal

Precious opal with play of color (commonly red or green) displayed against
a dark gray (rarely black) body color; e.g., the fine Australian blue opal
with flame-colored flashes.




black ore

a. Eng. Partly decomposed pyrite containing copper. Fay
b. In uranium mining, the term may mean ore containing a high proportion
of pitchblende, uraninite, coffinite, or vanoxite.
c. Cumb. A variety of hematite in hard pieces, some kidney shaped,
reaching the size of one's hand, in a moderately soft, dark-red, brown, or
nearly black mass of smit clay and manganese oxide, the whole having a
most confused appearance.




black oxide of manganese

See:pyrolusite




black pigment

Lampblack obtained by burning common coal tar. Fay




black powder

A deflagrating or low-explosive granular compound of sulfur, charcoal, and
an alkali nitrate, usually potassium or sodium nitrate.
Syn:black gunpowder




black roast

In fluidization roasting (fluosolids process), the conversion of iron
sulfide to magnetite. Pryor, 3




black rouge

A precipitated black magnetic iron oxide. Used mainly in plate printing
inks and in paints, but has small abrasive applications.
See also:black magnetic rouge




black sand

a. An alluvial or beach sand consisting predominantly of grains of heavy,
dark minerals or rocks (e.g., magnetite, rutile, garnet, or basaltic
glass), concentrated chiefly by wave, current, or surf action. It may
yield valuable minerals. See also:beach placer
b. An asphaltic sand. AGI




black shale

a. A dark, thinly laminated carbonaceous shale, exceptionally rich in
organic matter (5% or more carbon content) and sulfide (esp. iron sulfide,
usually pyrite), and often containing unusual concentrations of certain
trace elements (U, V, Cu, Ni). It is formed by partial anaerobic decay of
buried organic matter in a quiet-water, reducing environment (such as in a
stagnant marine basin) characterized by restricted circulation and very
slow deposition of clastic material. Fossil organisms are preserved as a
graphitic or carbonaceous film or as pyrite replacements.
Syn:biopelite
b. Usually a very thin-bedded shale, rich in sulfides (esp. pyrite, which
may have replaced fossils) and rich in organic material, deposited under
barred basin conditions causing anaerobic accumulation. AGI
c. Generally, a fine-grained, finely laminated carbonaceous shale,
sometimes canneloid, often found as a roof to a coal, or in place of a
coal, resting on a fire clay. Syn:black metal




black silver

See:stephanite




black smoker

A hydrothermal vent at the crest of an oceanic ridge; e.g., the East
Pacific Rise at the mouth of the Gulf of California. Waters blackened by
sulfide precipitates jet out at 1 to 5 m/s at temperatures of at least 350
degrees C. The term refers to uprushing black turbulent suspension.
CF:white smoker




black telluride

See:nagyagite




black tellurium

a. A rare gray metallic mineral, a sulfotelluride of gold and lead with
some antimony. CTD
b. See:nagyagite




black tin

Eng. Dressed tin ore ready to be smelted; from Cornwall.
See also:cassiterite




black wad

An early name for several minerals, including graphite and the softer
manganese oxides.




bladder pump

A positive displacement pump in which compressed air is forced down an
input column to squeeze a water-filled bladder, thereby forcing water up a
discharge column to the ground surface. The bladder refills by gravity
flow at the end of each lifting cycle, because the bladder unit is below
the static water lever. See:positive displacement pump.




blade

a. The shape of a solid, as one in which the ratios of breadth to length
and thickness to breadth are each less than 2:3.
b. Having the appearance of blades, e.g., flat crystals strongly elongated
in one direction.




bladed

Decidedly elongated and flattened; descriptive of some minerals.
Fay


bladed structure

Consisting of individual minerals flattened like a knife blade.
Hess




blade mill

Trommel washer with lifting blades, which aid in disintegration and
scrubbing of passing feed. Pryor, 3




blaes

a. A Scottish term for a gray-blue carbonaceous shale that weathers to a
crumbly mass and eventually to a soft clay. See also:bind
b. A Scottish term for a hard, joint-free sandstone. Syn:blaize
AGI




Blair process

An improved form of the Chenot process for making sponge iron by heating
crushed iron oxide and coal in retorts.




Blaisdell excavator

An apparatus for automatically discharging a sand tank having a central
bottom opening. It consists of a central vertical shaft carrying four arms
fitted with round plow disks. Sand is plowed toward a central opening and
discharged on a conveyor belt. Syn:Blaisdell vat excavator
Liddell; Fay




Blaisdell loading machinery

An apparatus for loading sand tanks. It consists of a rapidly revolving
disk with curved radial vanes. The disk is hung on a shaft in the tank
center, and the sand dropped on the disk is distributed over the entire
tank area. Liddell




Blaisdell vat excavator

See:Blaisdell excavator




blaize

See:blaes




Blake breaker

A jaw breaker or particular kind of jaw crusher. Nelson




Blake furnace

A furnace, the hearth of which consists of terraces rising from the outer
edge to the center. The hearth is circular and revolves when in operation.
Fay




blakeite

a. Anhydrous ferric tellurite as reddish-brown microcrystalline (cubic?)
crusts from Goldfield, NV. Spencer, 3
b. Titanozirconate of thorium, uranium, calcium, iron, etc., described as
zirkelite from Ceylon [now Sri Lanka], but differing in chemical
composition and also apparently in crystalline form from the original
zirkelite from Brazil. Spencer, 4




Blake jaw crusher

The original crusher of jaw type. A crusher with one fixed jaw plate and
one pivoted at the top so as to give the greatest movement on the smallest
lump. Motion is imparted to the lower end of the crushing jaw by toggle
joint operated by eccentric. This machine, or some modification of it, is
used for reducing run-of-mine ore or coal to a size small enough to be
taken by the next crusher in the series during the first stage of
crushing. Liddell; Newton, 1




Blake Morscher separator

See:electrostatic separator




blank

a. An interval in a borehole from which core was not recovered or was
lost, or in which no minerals of value were encountered. Long
b. See:bit blank
c. In powder metallurgy, a pressed, presintered, or fully sintered
compact, usually in the unfinished condition and requiring cutting,
machining, or some other operation to produce the final shape.
ASM, 1
d. A quartz plate with approx., or exactly, the correct edge dimensions,
but not yet finished to final thickness (frequency). Ordinarily applied to
pieces of quartz that are in the process of being machine lapped or that
are diced out, but not yet lapped. Am. Mineral., 2




blank bit

See:bit blank




blanket

a. A textile material used in ore treatment plants for catching coarse
free gold and some associated minerals; e.g., pyrite. The blanket is taken
up periodically and washed in a tub to remove the gold concentrate, from
which the gold is recovered by amalgamation. CF:tabular
b. See:blanket deposit; blanket vein.
c. Soil or broken rock left or placed over a blast to confine or direct
throw of fragments. Nichols, 1
d. A thin, widespread sedimentary body whose width-thickness ratio is
greater than 1,000:1 and may be as great as 50,000:1. Syn:sheet
AGI




blanket deposit

a. A horizontal, tabular orebody; manto; bedded vein. AGI
b. A sedimentary deposit of great areal extent and relatively uniform
thickness; esp. a blanket sand and associated limestones.
See also:blanket; blanket vein. AGI




blanket feed

A method for charging batch designed to produce an even distribution of
batch across the width of the furnace. ASTM




blanketing

a. The material caught upon the blankets used in concentrating
gold-bearing sands or slimes; also the process involved.
b. Can. Staking but not recording claims. Hoffman




blanket sand

A blanket deposit of sand or sandstone of unusually wide distribution,
typically an orthoquartzitic sandstone deposited by a transgressive sea
advancing for a considerable distance over a stable shelf area; e.g., the
St. Peter Sandstone of the East-Central United States. Syn:sheet sand;
blanket sandstone. AGI




blanket sandstone

See:blanket sand


blanket shooting

Applied to a method of blasting on a face not exceeding 30 ft or 35 ft
(9.1 m or 10.7 m) in height. It involves leaving at the quarry face a mass
of shattered rock several feet in thickness that serves as a buffer,
preventing the rock from being thrown far from its source, and also
rendering the shot more effective. Syn:buffer shooting;
shooting against the bank. Fay




blanket sluice

A sluice in which coarse blankets are laid to catch the fine but heavy
particles of gold, amalgam, etc., in the slime passing over them. The
blankets are removed and washed from time to time to obtain the precious
metal. Fay




blanket strake

A trough over which gold pulp flows. It is lined with a blanket for
catching coarse gold and associated minerals. See also:strake
Nelson




blanket vein

A horizontal or sheet deposit. See also:blanket; blanket deposit.
CF:bed vein




blanket washer

In ore dressing, smelting, and refining, one who cleans flannel blankets
over which a mixture of finely ground gold ore and cyanide solution from
Chilean mills is passed to collect free particles of gold not dissolved by
the cyanide. DOT




blank hole

a. A borehole in which no minerals or other substances of value were
penetrated. Syn:barren hole; dry hole. Long
b. The uncased portion of a borehole. Syn:bare; barefoot; naked.
Long




blankoff

To line a specific portion of a borehole with casing or pipe for the
purpose of supporting the sidewalls or to prevent ingress of unwanted
liquids or gas. Syn:case; case off CF:seal off




blank pipe

Unperforated pipe or casing set in a borehole. Long




blank reaming shell

A reaming shell in which no reaming diamonds or other cutting media are
inset on the outside surface. Long




Blanton cam

A device used for locking the cam on the camshaft in a stamp mill.
Fay




Blasjo cut

This is a cut with a single V where all the holes on one side are parallel
and meet the holes from the other side at an angle that may be as low as
30 degrees . Langefors




blast

a. The ignition of a heavy explosive charge. Syn:shot
b. A miner's term for compressed air underground. Nelson
c. Scot. A fall of water in the downcast shaft to produce or quicken
ventilation.
d. A suffix signifying a texture formed entirely by metamorphism.
AGI
e. The operation of increasing the diamond exposure on a bit face by
removing some of the matrix metal through the abrasive action of grains of
sand carried in a high-pressure stream of air. Also called sandblast.
Long
f. An increase in firing temperature of a kiln immediately before ending
the firing operation.
g. The period during which a blast furnace is in blast; i.e., in
operation.




blast coupling

The degree to which an explosive fills the borehole. Bulk-loaded
explosives are completely coupled. Untamped cartridges are decoupled.
Dick, 2




blast draft

The draft produced by a blower, as by blowing in air beneath a fire or
drawing out the gases from above it. A forced draft. Fay




blaster

a. A device for detonating an explosive charge. AGI
b. One who sets off blasts in a mine or quarry. A shot firer.
Syn:shooter
c. See:blasting unit




blast furnace

A shaft furnace in which solid fuel is burned with an airblast to smelt
ore in a continuous operation.




blast furnace dust

A dust recovered from blast furnace gases, some of which is valuable for
its potash content. Hess




blast furnace gas

A low-grade producer gas, made by the partial combustion of the coke used
in the furnace and modified by the partial reduction of iron ore. The gas
contains more carbon dioxide and less hydrogen than normal producer gas
made from coke and has a lower calorific value. Francis, 2




blast-furnace slag

The nonmetallic product, consisting essentially of silicates and
aluminosilicates of lime and of other bases, that is developed
simultaneously with iron in a blast furnace. Syn:slag




blast hearth

A hearth in connection with which a blast is used, as in reducing lead
ore. Fay




blasthole

A hole drilled in a material to be blasted, for the purpose of containing
an explosive charge.


blasthole charger

A portable unit consisting of a prilled explosive reserve tank feeding
into an air-activated loading tube. The equipment should be grounded to
guard against buildup of static electricity and possible accidental
explosive detonation. The blasthole charger permits rapid loading of
prilled explosives into blastholes drilled in any direction.




blasthole drill

Any rotary, percussive, fusion-piercing, churn, or other type of drilling
machine used to produce holes in which an explosive charge is placed.
Syn:shothole drill




blasthole driller

See:churn-drill operator




blasting agent

An explosive material that meets prescribed criteria for insensitivity to
initiation. It is a material or mixture consisting of fuel and oxidizer
used in blasting, but not otherwise defined as an explosive. The finished
mixture used for shipment or transportation cannot be detonated by a No. 8
test detonator cap when unconfined.




blasting barrel

A piece of iron pipe, usually about 1/2 in (1.3 cm) in diameter, used to
provide a smooth passageway through the stemming for the miner's squib. It
is recovered after each blast and used until destroyed. Fay




blasting cap

a. A detonator containing an ignition explosive mixture, a primary
initiating charge, and a high-explosive base charge, encapsulated in an
aluminum or copper shell. Caps are initiated either electrically or
nonelectrically. See also:waterproof electric blasting cap
b. A small sensitive charge placed in the larger explosive charge by which
the larger charge is detonated. See also:electric detonator
BCI




blasting cartridge

A cartridge containing an explosive to be used in blasting. Fay




blasting circuit

A shotfiring cord together with connecting wires and electric blasting
caps used in preparation for the firing of a blast in mines, quarries, and
tunnels.




blasting compounds

Explosive substances used in mining and quarrying. Hess




blasting cord

See:shot-firing blasting cord




blasting curtain

A screen erected to prevent damage to equipment and supports in the
vicinity of the blasting point. See also:curtain; shot-firing curtain.
Syn:blasting cord




blasting fuse

a. A slow-burning fuse used in blasting operations. Standard, 2
b. A fine core of gunpowder enclosed in the center of jute, yarn, etc.,
for igniting an explosive charge in a shothole. See also:safety fuse
Nelson




blasting galvanometer

An instrument that provides a simple means for testing electric blasting
circuits, enabling the blaster to locate breaks, short circuits, or faulty
connections before an attempt is made to fire the shot. With its use,
misfires may be prevented to a great extent. To test a circuit, one wire
should be placed on one terminal of the instrument and the other wire on
the other terminal. If the needle is not deflected, it indicates that the
circuit is broken; if it is an electric blasting cap that is being tested,
this should be discarded. Pit and Quarry




blasting gelatin

A high explosive, consisting of nitroglycerin and nitrocotton. It is a
strong explosive, and a rubberlike, elastic substance, unaffected by
water. Taken as a standard of explosive power. CF:dynamite
Fay; BS, 12




blasting hole well driller

See:churn-drill operator




blasting log

A written record of information about a specific blast as may be required
by law or regulations. Atlas




blasting machine

A portable dynamo that generates enough electric current to detonate
electric blasting caps when the machine rack bar or handle is given a
quick, downward push. Syn:battery
M.E. 6 exploder. Long




blasting mat

A mat of woven steel wire, rope, scrap tires, or other suitable material
or construction to cover blastholes for the purpose of preventing flying
rock missiles. Meyer




blasting needle

A pointed instrument for piercing the wad or tamp of a charge of
explosive, to permit introducing a blasting fuse. Standard, 2




blasting off the solid

Blasting the working face in a coal mine without providing a second free
face by cutting or shearing before blasting. CFR, 4




blasting oil

See:nitroglycerin

blasting reflection mechanism

See:reflection mechanism




blasting supplies

A term used to include electric blasting caps, ordinary blasting caps,
fuse, blasting machines, galvanometers, rheostats, etc., in fact,
everything used in blasting, except explosives. CF:blowing tools
Fay




blasting switch

A switch used to connect a power source to a blasting circuit. It is
sometimes used to short-circuit the leading wires as a safeguard against
premature blasts.




blasting timer

An instrument that utilizes a powerline as a source of electrical current
and that closes the circuits of successive blasting caps with a delay time
interval. The timer provides for the circuits of 15 charges and affords
positive control of the duration of intervals. Streefkerk




blasting tube

A tube of explosives, as nitroglycerin, for blasting. Standard, 2




blasting unit

A portable device including a battery or a hand-operated generator
designed to supply electric energy for firing explosive charges in mines,
quarries, and tunnels. Syn:blaster; exploder; shot-firing unit.
See also:single-shot blasting unit; multiple-shot blasting unit.




blasting vibrations

The energy from a blast that manifests itself in earthborne vibrations
that are transmitted through the Earth away from the immediate blast site.
Syn:ground vibrations




blast nozzle

A fixed- or variable-sized outlet of a blast pipe. Fay




blastogranitic

A relict texture in a metamorphic rock in which remnants of the original
granitic texture remain. AGI




blastophitic

Said of a relict texture in a metamorphic rock in which traces of an
original ophitic texture remain. AGI




blastoporphyritic

Said of a relict texture in a metamorphic rock in which traces of an
original porphyritic texture remain. AGI




blast pattern

The array of drilled holes on the surface or underground to be loaded and
detonated in sequence; a pattern is indicated by the distance between
holes in a row (spacing) and between rows (burden).




blast roasting

Roasting conducted in a Dwight-Lloyd machine, in which roasting is
accompanied by sintering. The charge is placed in small boxes and ignited;
air is then drawn through to burn off sulfur.
Syn:Carmichel-Bradford process




blast site

The area where explosive material is handled during the loading and
detonation of blast holes; in surface blasting, it includes 50 ft (15.2 m)
in all directions from perimeter holes; underground, it includes 15 ft
(4.6 m) of solid rib. Atlas




bleaching clay

A clay or earth that, either in its natural state or after chemical
activation, has the capacity for adsorbing or removing coloring matter or
grease from liquids (esp. oils). Syn:bleaching earth




bleaching earth

See:bleaching clay




bleb

A small, usually rounded inclusion of one mineral in another; e.g., blebs
of olivine poikilitically enclosed in pyroxene.




bled ingot

In steelmaking, an ingot that has lost its molten center while cooling.
Standard, 2




bleeder

a. A connection located at a low place in an air line or gas line, or
container, so that by means of a small valve the condensed water or other
liquid can be drained or bled off from the line or container without
discharging the air or gas. Long
b. A fine-adjustment valve (needle valve) connected to the bottom end of a
hydraulic feed cylinder in the swivel head of a diamond drill. By means of
the bleeder, the speed at which the hydraulic piston travels can be
minutely controlled. Long
c. A pipe on top of an iron blast furnace through which gas escapes.




bleeder entries

Widely used for draining methane in coal mines in the United States where
the room-and-pillar method is employed. They are panel entries driven on a
perimeter of a block of coal being mined and maintained as exhaust airways
to remove methane promptly from the working faces to prevent buildup of
high concentrations either at the face or in the main intake airways. They
are maintained, after mining is completed, in preference to sealing the
completed workings. Hartman, 1




bleeder pipe

A pipe inserted in a seal to relieve gas pressure from a sealed area.


bleeding

a. The process of giving off oil or gas from pore spaces or fractures; it
can be observed in drill cores. AGI
b. The exudation of small amounts of water from coal or a stratum of some
other rock. AGI




bleeding surface

Any face, such as the walls of a well or borehole or the sides of a
fracture, that traverses a reservoir rock or aquifer, permitting the
stored liquid or gas to seep (or to bleed) into the opening. AGI




bleed off

A coal mining term used when feeders or blowers act as the means by which
gas is "bled off" or dissipated to the adjoining strata or to the surface.
Kentucky




blende

a. Without specific qualification, it means zincblende or the sulfide of
zinc (sphalerite), which has the luster and often the color of common
resin and yields a white streak and powder. The darker varieties are
called blackjack by English miners. Other minerals having this luster are
also called blendes, such as antimony blende, ruby blende, pitchblende,
and hornblende. Sphalerite (blende) is often found in brown shining
crystals, hence its name among German miners, from the word blenden,
meaning to dazzle. Fay
b. A miners' term for sphalerite.
c. Various minerals, chiefly metal sulfides, with bright or resinous but
nonmetallic luster, e.g., zinc blende (sphalerite), antimony blende
(kermesite), bismuth blende (eulytite), cadmium blende (greenockite),
pitchblende (uraninite), hornblende.




blended unconformity

An unconformity having no distinct surface of separation or sharp contact,
as at an erosion surface that was originally covered by a thick residual
soil, which graded downward into the underlying rocks and was partly
incorporated in the overlying rocks; e.g., a nonconformity between granite
and overlying basal arkosic sediments derived as a product of its
disintegration. Syn:graded unconformity




blending

Mixing in predetermined and controlled quantities to give a uniform
product. BS, 5




blending conveyor

A conveyor running beneath a line of ore bins or stockpiles, and so set
that each bin or stockpile can deliver onto the conveyor at a controllable
rate from individual feeders. Syn:paddle-type mixing conveyor;
screw-type mixing conveyor. Pryor, 3




blind

a. To drill with the circulation medium (water or drill mud) escaping into
the sidewalls of the borehole and not overflowing the collar of the drill
hole. Long
b. An underground opening not connected with other workings nearby and at
about the same elevation. Long
c. Said of a mineral deposit that does not crop out. The term is more
appropriate for a deposit that terminates below the surface than for one
that is simply hidden by unconsolidated surficial debris.
Syn:blind vein




blind apex

The near-surface end of a mineral deposit, e.g., the upper end of a seam
or vein that is truncated by an unconformity. Syn:buried outcrop
AGI




blind bit

See:noncoring bit




blind borehole process

In the underground gasification of coal, a borehole is drilled to a blind
end having no outside connection. A tube of smaller diameter is inserted
nearly the full length through which air is passed to supply a
gasification reaction at the far end of the hole. The hot gases return
around the outside of the tube. See also:underground gasification
Nelson




blind drift

A horizontal passage, in a mine, not yet connected with the other
workings. See also:blind level




blinde

See:blende




blind header

A concealed brick header in the interior of a wall, not showing on the
faces. ACSG, 1




blind hole

A borehole in which the circulating medium carrying the cuttings does not
return to the surface. Long




blinding

a. In leaching, reduced permeability of ion-exchange resins due to
adherent slimes. In sieving, blocking of screen apertures by particles.
Pryor, 3
b. A matting of, or stoppage by, fine materials during screening that
interferes with or blinds the screen mesh.
c. Compacting soil immediately over a tile drain to reduce its tendency to
move into the tile. Nichols, 1




blind joint

In apparently massive rock that is being quarried, a plane of potential
fracture along which the rock may break during excavation. AGI




blind lead

A vein having no outcrop. See also:blind lode; blind vein; lead.




blind level

a. One not yet holed through to connect with other passages.
Syn:blind drift
b. A cul-de-sac or dead end. Pryor, 3
c. A level for drainage, having a shaft at either end, and acting as an
inverted siphon.




blind lode

A lode showing no surface outcrop, and one that cannot be found by any
surface indications. See also:blind lead; blind vein.




blind road

Mid. Any underground roadway not in use, having stoppings placed across
it. Syn:blind way


blind roaster

A muffle furnace for roasting ore out of contact with the products of
combustion. Standard, 2




blind seams

Incipient joints.




blind shaft

A sublevel shaft, connected to the main (daylight to depth) shaft by a
transfer station. A winze. Pryor, 3




blind shearing

Scot. A side cutting without undercutting.




blind vein

A vein that does not continue to the surface. See also:blind;
blind lode; blind lead. Fay




blind way

See:blind road




blind zone

See:shadow zone




blip

Echo trace on radar or sonar indicator screen. Hy




Bliss sandstone

Massive, compact, fine-textured, fossiliferous gray sandstone ranging from
almost white to brown. It may be either Cambrian or Ordovician, or both,
at any given locality. It represents a period of slow intermittent
deposition of sandy material. Found in New Mexico and in Texas.
Hess




blister

a. In quarrying, an unconfined charge of explosive used to bring down
dangerous ground that cannot be made safe by barring and that is too
inaccessible to bore. South Australia
b. A protrusion, more or less circular in plan, extending downward into a
coal seam. It represents the filling of a streambed pothole worn into the
upper surface of the coal-forming material. AGI
c. Copper as a smelter product before it is refined. Hoffman
d. A defect in metal, on or near the surface, resulting from the expansion
of gas in a subsurface zone. Very small blisters are called pinheads or
pepper blisters. ASM, 1




blister bar

A wrought-iron bar impregnated with carbon by heating in charcoal. Used in
making crucible steel. CTD




blister copper

An impure intermediate product in the refining of copper, produced by
blowing copper matte in a converter. ASM, 1




blistered copper ore

A reniform variety of chalcopyrite. Fay




blister steel

Raw steel that has been cooled very slowly and that has a blistered
appearance. The blisters are formed by gas escaping from within the metal.
Camm




blister wax

See:blower wax




bloating phenomena

The expansion of certain nonmetallic materials by heating until the
exterior of the particle or shape becomes sufficiently pyroplastic or
melted to entrap gases generated on the interior by the decomposition of
gas-producing components.




block

a. A division of a mine, usually bounded by workings but sometimes by
survey lines or other arbitrary limits.
b. A short piece of timber placed between the mine roof and the cap of a
timber set and directly over the cap support. A wedge driven between the
roof and the timber holds the set in place.
See also:blocking and wedging
c. A pillar or mass of ore exposed by underground workings.
See also:blocking out
d. Portion of an orebody blocked out by drives, raises, or winzes, so that
it is completely surrounded by passages and forms a rectangular panel. If
its character, volume, and assay grade are thus established beyond
reasonable doubt, it ranks as proved ore in the mine's assets.
Pryor, 3
e. The wedging of core or core fragments or the impaction of cuttings
inside a bit or core barrel, which prevents further entry of core into the
core barrel, thereby producing a condition wherein drilling must be
discontinued and the core barrel pulled and emptied to forestall loss of
core through grinding or the serious damage of the bit or core barrel.
See also:core block; plug. Long
f. An obstruction in a borehole. Long
g. See:sheave




block caving

A general term that refers to a mass mining system where the extraction of
the ore depends largely on the action of gravity. By removing a thin
horizontal layer at the mining level of the ore column, using standard
mining methods, the vertical support of the ore column above is removed
and the ore then caves by gravity. As broken ore is removed from the
mining level of the ore column, the ore above continues to break and cave
by gravity. The term "block caving" probably originated in the porphyry
copper mines, where the area to be mined was divided into rectangular
blocks that were mined in a checkerboard sequence with all the ore in a
block being removed before an adjacent block was mined. This sequence of
mining is no longer widely used. Today most mines use a panel system,
mining the panels sequentially or by establishing a large production area
and gradually moving it forward as the first area caved becomes exhausted.
The term "block caving" is used for all types of gravity caving methods.
There are three major systems of block caving, and they are differentiated
by the type of production equipment used. (1) The first system based on
the original block cave system is the grizzly or gravity system and is a
full gravity system wherein the ore from the drawpoints flows directly to
the transfer raises after sizing at the grizzly and then is gravity loaded
into ore cars. (2) The second system is the slusher system, which uses
slusher scrapers for the main production unit. (3) The last system is the
rubber-tired system, which uses load-haul-dump (LHD) units for the main
production unit. Block caving has the lowest cost of all mine exploitation
systems, with the exception of open pit mining or in situ recovery.
See also:top slicing




block caving into chutes

See:chute caving




block claim

Aust. A square mining claim whose boundaries are marked out by posts.




block diagram

A plane figure representing a block of the Earth's crust (depicting
geologic and topographic features) in a three-dimensional perspective,
showing a surface area on top and including one or more (generally two)
vertical cross sections. The top of the block gives a bird's-eye view of
the ground surface, and its sides give the underlying geologic structure.
AGI


blocked-out ore

a. Ore, the amount, content, and minability of which have been proven by
development work or by drilling developed ore. Syn:developed reserve
AGI
b. A body of ore exposed, explored, and sampled for valuation purposes on
all four sides of the panel formed by driving, winzing, and raising.
Pryor, 3
c. See:reserves




block faulting

A type of normal faulting in which the crust is divided into structural or
fault blocks of different elevations and orientations. It is the process
by which block mountains are formed. AGI




block field

A thin accumulation of usually angular blocks, lying on bedrock without a
cliff or ledge above as apparent source. Block fields occur on high
mountain slopes above the tree line. Syn:felsenmeer




block hole

a. A small hole drilled into a rock or boulder into which an anchor bolt
or a small charge or explosive may be placed. Long
b. Used by drillers, miners, and quarry workers for a method of breaking
undesirably large blocks of stone or boulders by the discharge of an
explosive loaded into shallow holes drilled into the blocks or boulders.
Long
c. A relief hole designed to remove part of the burden from a subsequent
shot; used in coal mining.




blockholer

A person whose duty it is to break up and reduce to safe and convenient
size, by blasting or otherwise, any large blocks or pieces of rock that
have been blown down by the miners. Fay




block hole shot

See:pop shot




blockholing

The breaking of boulders by loading and firing small explosive charges in
small-diameter drilled holes.




blocking

In a crusher, obstruction of the crushing zone by clayey material or by
rock that refuses to break down and pass to discharge. Syn:packing




blocking and wedging

A method of holding mine timber sets in place. Blocks of wood are set on
the caps directly over the post supports and have a grain of block
parallel with the top of the cap; wedges are driven tightly between the
blocks and the roof. See also:block




blocking out

a. Exposing an orebody by means of development openings, on at least three
sides, in preparation for continuous extraction; the opening of a deep
lead deposit. See also:block
b. As applied to coal reserves, acquiring coal and mining rights in
contiguous areas to form a continuous area and in a desirable shape for
planned future mining.
c. Aust. Laying or staking out gold-bearing gravel deposits in square
blocks in order to facilitate systematic washing.
d. In economic geology, delimitation of an orebody on three sides in order
to develop it, i.e., to make estimates of its tonnage and quality. The
part so prepared is an ore block. AGI




block kriging

Estimating the value of a block from a set of nearby sample values using
kriging.




blockmaking

Applied to the various processes involved in roofing slate manufacture,
which include drilling and wedging, cutting, sawing, etc. AIME, 1




block mica

Mica with a minimum thickness of 0.007 in (0.18 mm) and a minimum usable
area of 1 in2 (6.45 cm2 ), full trimmed unless otherwise
specified. Skow




block mountain

A mountain that is formed by block faulting. The term is not applied to
mountains that are formed by thrust faulting. Syn:fault-block mountain
AGI




block movement

A general failure of the hanging wall. In the gold mines of South Africa
and the Michigan copper mines, block movements have been experienced.
Nelson




block off

a. To fill and seal undesirable openings, fissures, or caving zones in a
borehole by cementation or by lining the borehole with pipe or casing.
Also called blank off; case off; seal off. Long
b. To secure a mine opening against the flow or escape of gas, air, or
liquid by erecting rock, concrete, steel, wood, or cloth barriers.
Long
c. To erect barriers to prevent workers from entering unsafe areas in
underground workings. Long




block out

To delineate the area in which a desirable mineral occurs by systematic
core drilling or by underground openings. Long




block riffles

These consist of timber blocks, 8 to 12 in (20.3 to 30.5 cm) square, set
in transverse rows in a sluicebox; they are arranged so that in contiguous
rows the joints are staggered to prevent the development of longitudinal
cracks. It is usual to separate adjacent rows by means of a strip of
ordinary riffle scantling. Griffith




block structure

Used in quarrying to describe granite that has three sets of joints
occurring at right angles to each other. Streefkerk




block system

a. A pillar mining system in which a series of entries, panel entries,
rooms, and crosscuts are driven to divide the coal into blocks of approx.
equal size, which are then extracted on retreat. Development openings are
most commonly driven between 15 ft and 20 ft (4.6 m and 6.1 m) wide.
Pillars are most commonly 40 to 60 ft (12.2 to 18.3 m) wide and from 60 to
100 ft (18.3 to 30.5 m) long. Woodruff
b. A system of control in which a number of units, for example, powered
supports, are operated as a group. NCB




block system of stoping and filling

See:overhand stoping; Brown panel system.


block-tin lining

Copper vessels are lined or coated with tin by the application of molten
tin upon clean copper with the aid of fluxing. CCD, 2




blocky rock

Rock ore that breaks into large blocks. Sandstrom




bloedite

A monoclinic mineral, Na2 Mg(SO4 )2 .4H2 O .
Also spelled bloedite, blodite. Formerly called astrakhanite.
Syn:astrakanite; magnesium blodite.




Bloman tube breathing apparatus

This differs from the smoke helmet in that there is neither helmet nor
bellows. Fresh air is passed to the wearer through a corrugated reinforced
rubber tube by means of a rotary blower. A mouthpiece having an inhalation
valve, an exhalation valve, and a noseclip takes the place of the helmet.
It is held in position by straps attached to a head harness. The
mouthpiece can be replaced by a full-face mask. This apparatus is fitted
with an equalizing device that enables the wearer to continue breathing
comfortably, even should the rotary blower stop. Mason




blomstrandine

See:priorite




bloodstone

a. A variety of chalcedony or jasper, dark green in color, interspersed
with small red spots. Used as a gem. Also called heliotrope. CF:plasma
Sanford
b. A red variety of quartz.




blooey line

A pipe or flexible tube conducting cuttings-laden air or gas from the
collar of a borehole to a point far enough removed from the drill rig to
keep the air around the drill dust free. Long




bloom

a. A mineral that is frequently found as an efflorescence, cobalt bloom,
for example. Syn:efflorescence
b. To form an efflorescence; as, salts with which alkali soils are
impregnated bloom out on the surface of the Earth in dry weather following
rain or irrigation. Webster 2nd
c. The fluorescence of petroleum or its products. Webster 3rd
d. A semifinished hot-rolled product, rectangular in cross section,
produced on a blooming mill. For iron and steel, the width is not more
than twice the thickness, and the cross-sectional area is usually not less
than 36 in2 (232 cm2 ). Iron and steel blooms are
sometimes made by forging. ASM, 1
e. A surface film resulting from attack by the atmosphere or from the
deposition of smoke or other vapors. ASTM
f. A lump or mass of molten glass. Webster 2nd




bloomer

See:blooming mill




bloomery

A forge for making wrought iron, usually direct from the ore.
Syn:cinder plate; Merrit plate. Fay




blooming mill

The mill or equipment used in reducing steel ingots to blooms.
ASM, 1




blow

a. A sudden escape of gas from coal or associated strata into mine
workings. See also:outburst
b. A large outcrop of ore, commonly of low grade. Nelson
c. To lift: said of a floor that lifts owing to pressure from gas or
strata. Mason
d. In blasting, a shot that blows part of the unfired explosive out of the
hole. See also:blown-out shot
e. To fire shots. Mason




blow count

The number of blows that must be delivered by a specific-weight, freely
falling drive hammer dropping a specific distance to force a drive sampler
a unit distance into a soil material. Long




blower

a. A fan employed in forcing air either into a mine or into one portion of
a mine. A portable blower, also known as a tubing blower or room blower,
is used in ventilating small dead-end places like rooms and entries or
gangways. Jones, 1
b. The sudden emission of combustible gases from the coal seam or
surrounding rock. Blowers vary considerably in violence and magnitude from
small emissions that make a hissing noise to severe outbursts.
Nelson
c. Eng. A worker who blasts or fires shots in a mine, or who drills the
holes and charges them, ready for firing. Fay




blower fan

A fan to direct part of an air circuit through a tubing to a particular
working face. See also:mine ventilation auxiliary fan




blower system

A system in which the pressure-generating source is located at the
entrance and raises the pressure of the air above atmospheric.
Hartman, 2




blower wax

A pale yellow, soft variety of ozocerite that is squeezed out of the veins
under the influence of pressure of the surrounding rocks.
Syn:blister wax




blowhole

a. A minute crater formed on the surface of thick lava flows. Fay
b. A hole in a casting or a weld caused by gas entrapped during
solidification. See also:gas evolution




blow in

To put a blast furnace in operation. Syn:blowing in




blowing

a. Oxidation of molten metal or matte in a converter or other smelting
furnace, in order to remove carbon and sulfur and to convert impurities to
slag.
b. The bursting of pots from too rapid heating. ACSG, 2




blowing engine

An engine for forcing air into blast furnaces under pressure, commonly
about 1 psi (6.9 kPa). Weed, 2


blowing in

Starting a blast furnace. Syn:blow in




blowing on taphole

Blowing air through the hole at casting, to clean the hearth of iron and
cinder. Fay




blowing road

S. Staff. An intake, or fresh-air road in a mine.




blowing tools

A small set of blasting implements. CF:blasting supplies
Standard, 2; Fay




blowing-up furnace

A furnace used for sintering ore and for the volatilization of lead and
zinc. Fay




blowing ventilation

Mine ventilation in which the air flows from the fan at the portal toward
the working face.




blown metal

Pig iron purified by blowing air through it.




blown-out shot

A shot that dissipates the explosive force by blowing out the stemming
instead of breaking down the coal. It may be caused by insufficient
stemming, overcharging with explosive, or a burden that is too much for
the charge to dislodge. See also:gun; blow. Syn:cannon shot;
gunned shot. Nelson




blowout

a. A large mineralized outcrop beneath which the vein is smaller, e.g., a
great mass of quartz that conceals a vein only a few feet wide.
b. A shot or blast that goes off like a gun and does not shatter the rock;
a windy shot.
c. A large outcrop beneath which the vein is smaller is called a blowout.
(slang) Fay
d. The high-pressure, sometimes violent, and uncontrolled ejection of
water, gas, or oil from a borehole. Long
e. Used by prospectors and miners for any surface exposure of strongly
altered discolored rock associated, or thought to be associated, with a
mineral deposit. AGI
f. Used by miners and prospectors for a large, more or less isolated,
usually barren quartz outcrop. Known in Australia as blow. Hess
g. To put a blast furnace out of blast, by ceasing to charge fresh
materials, and continuing the blast until the contents of the furnace have
been smelted. Fay
h. To smelt the iron-bearing materials in the furnace, adding domestic
coke so that the stockline is about normal. Camp
i. A general term for a small saucer-, cup-, or trough-shaped hollow or
depression formed by wind erosion on a preexisting dune or other sand
deposit, esp. in an area of shifing sand or loose soil, or where
protective vegetation is disturbed or destroyed; the adjoining
accumulation of sand derived from the depression, where recognizable, is
commonly included. Some blowouts may be many kilometers in diameter.
AGI




blowout shot

An improperly placed or overcharged shot of black blasting powder in coal
(where used), frequently results in a mine explosion.
von Bernewitz




blowover

a. Sand blown by onshore winds across a barrier and deposited on its
landward side or as a veneer in the lagoon; e.g., along the Gulf Coast of
Texas. CF:washover
b. The process of forming a blowover. AGI




blowpipe reaction

a. The decomposition of a compound or mineral when heated by the blowpipe,
resulting in some characteristic reaction, as a coloring of the flame or a
colored crust on a piece of charcoal. Standard, 2
b. A method of analysis in mineralogy. Fay




blowpiping

a. A rapid method for the determination of the approximate composition of
minerals and ores. Blowpipe tests are merely qualitative; i.e., they
indicate the presence of the different constituents, but not the
proportions. A blowpipe consists of a plain brass tube capable of
producing a flame of intense heat that may be either oxidizing or
reducing. Illuminating gas from a Bunsen burner is the fuel commonly used.
The color, nature, and smell of the encrustations suggest the nature of
the elements present. See also:bead; borax bead test. Nelson
b. The use of a bent tube with a condensation trap and a small hole to
direct one's concentrated breath into a small flame from a gas or alcohol
lamp to produce intense heat in both oxidizing and reducing flames for the
purpose of soldering metals or of performing qualitative analyses on
powdered mineral samples. See also:oxidizing flame; reducing flame.




blowup

a. Eng. An explosion of combustible gases in a mine.
b. To allow atmospheric air access to certain places in coal mines, so as
to generate heat, and ultimately to cause gob fires.




blue annealing

Heating hot-rolled ferrous sheet in an open furnace to a temperature
within the transformation range, and then cooling it in air in order to
soften the metal. The formation of a bluish oxide on the surface is
incidental. ASM, 1




blue asbestos

A name for crocidolite, the asbestiform variety of riebeckite.




blue band

A thin, persistent bed of bluish clay that is found near the base of the
No. 6 coal throughout the Illinois-Indiana basin.




blue-black ore

Corvusite, extremely high-grade vanadium ore with blue-black color.
Ballard




blue brittleness

Brittleness exhibited by some steels after being heated to some
temperature within the range of 300 to 650 degrees F (149 to 343 degrees
C), particularly if the steel is worked at the elevated temperature.
ASM, 1




blue cap

The characteristic blue halo, or tip, of the flame of a safety lamp when
combustible gases are present in the air. See also:top; cap.




blue chalcedony

See:sapphirine


blue chalcocite

See:digenite




blue copper

See:azurite; covellite.




blue copper ore

See:azurite




blue earth

See:blue ground




blue gold

a. A gold-iron alloy containing 25% to 33.3% iron. Camm
b. A bluish collodial solution of gold prepared by reducing a solution of
gold chloride with hydrazine hydrate. Camm




blue granite

See:larvikite




blue ground

Unoxidized slate-blue or blue-green kimberlite, usually a breccia (as in
the diamond pipes of South Africa) that is found below the surficial
oxidized zone of yellow ground. CF:hardebank
AGI




blue iron earth

See:vivianite




blue ironstone

A bluish iron-bearing mineral; specif: crocidolite and vivianite.




blue lead

a. A term for metallic lead in the lead industry to distinguish it from
lead compounds with color designations, such as white lead, orange lead,
and red lead. See also:lead
b. A synonym of galena, esp. a compact variety with a bluish-gray color.
Syn:galena; blue lead ore. AGI
c. A bluish, gold-bearing lead or gravel deposit found in Tertiary river
channels of the Sierra Nevada, CA. Pronounced "blue leed." AGI




blue lead ore

An old name for a compact variety of galena with a bluish-gray color.
Pron: led.




blue malachite

An erroneous name for azurite.




blue metal

A term used in England for a hard bluish-gray shale or mudstone lying at
the base of a coalbed and often containing pyrite. AGI




blue mud

a. An ocean-bottom deposit containing up to 75% terrigenous materials of
dimensions below 0.03 mm. The depth range occurrence is about 750 to
16,800 ft (229 to 5,120 m). Colors range from reddish to brownish at the
surface, but beneath the surface, the colors of the wet muds are gray to
blue. AGI
b. A common variety of deep-sea mud having a bluish-gray color due to
presence of organic matter and finely divided iron sulfides. Calcium
carbonate is present in amounts up to 35%. AGI




blue needles

Applied in the grading of quartz crystals to needlelike imperfections,
often definitely oriented, which show up with a bluish-white color under
the carbon arc. The color is due to the selective scattering of blue light
by the minute imperfections. Am. Mineral., 2




blue ocher

See:vivianite




blue powder

A mixture of finely divided and partly oxidized metallic zinc formed by
the condensation of zinc vapor into droplets; also, any similar zinc
byproduct (such as dross, skimmings, or sweepings). Webster 3rd




blue quartz

See:sapphire quartz




blue-rock phosphate

The hard, bluish-gray, Ordovician bedded phosphates of central Tennessee.




blue room

The first room in a baghouse. Fay




blue schorl

a. Blue tourmaline. Fay
b. The earliest name for anatase (octahedrite).


blue spar

See:lazulite




bluestone

a. A commercial name for a building or paving stone of bluish-gray color;
specif. a dense, tough, fine-grained, dark blue-gray or slate-gray
feldspathic sandstone that splits easily into thin, smooth slabs and that
is extensively quarried near the Hudson River in New York State for use as
flagstone. The color is due to the presence of fine black and dark-green
minerals, chiefly hornblende and chlorite. The term is applied locally to
other rocks, such as dark-blue shale and blue limestone. CF:flagstone
AGI
b. A miners' term for chalcanthite.
c. A term applied locally to rocks such as dark-blue shale, blue
limestone, and bluish metabasalt (greenstone).
d. A highly argillaceous sandstone, of even texture and bedding, formed in
a lagoon or lake near the mouth of a stream.




blue tops

Grade stakes whose tops indicate finish grade level. Nichols, 1




blue vitriol

See:chalcanthite




blue-white diamond

A diamond that appears blue or bluish in transmitted white light or
against a white background; it reflects white light when viewed edge up at
right angles to the table. Hess




bluntin

Derb. A dark tough vein filling that dulls the drills readily.




Blyth elutriator

Laboratory apparatus in which mineral particles suspended in water are
syphoned through vertical tubes of increasing cross section, the fraction
failing to rise under determined conditions of upward flow reporting as a
subsieve fraction. Pryor, 3




BM

See:bench mark




B.M.A.G.A. apparatus

Used in the United States for obtaining additional information on the
yields of coke, tar, and gas that can be expected in high-temperature
practice. This is a vertical cylinder of mild steel holding up to 2
hundredweight (91 kg) of coal and operated at temperatures up to 1,000
degrees C. Francis, 2




board

See:bord




board-and-pillar

See:pillar-and-breast




board-and-wall

See:pillar-and-breast




board coal

Eng. Coal having a fibrous or woody appearance. Fay




board gates

York. Headings driven in pairs generally to the rise, out of which banks
or stalls are opened and worked. Hess




board of trade unit

The work done when a rate of working of 1 kW is maintained for 1 h. The
British unit of electrical energy; kilowatt-hour. Abbrev: B.O.T. unit.
Nelson




board run

The amount of undercutting that can be done at one setting of a coal
mining machine, usually about 5 ft (1.5 m), without moving forward the
board upon which the machine works. Fay




boart

See:bort




boartz

See:bort




boat

A gold dredge.




bobbin

a. Aust. A catch placed between the rails of the upline of an incline to
stop any runaway trucks. It consists of a bent iron bar, pivoted in such a
manner that the downhill end is slightly heavier than the uphill end,
which is capable of being depressed by an upcoming truck, but rises above
the level of the truck axle as soon as the truck is past. Syn:monkey;
monkey chock. Fay
b. A spool or reel. Fay




bocca

A volcanic crater or vent. Standard, 2


body

a. An orebody, or pocket of mineral deposit. Zern
b. See:bit blank
c. The fluidity of a drilling mud expressed in the number of seconds in
which a given quantity of mud flows through a given aperture, such as the
aperture in a Marsh funnel. Long
d. The term used to indicate the viscosity or fluidity of a lubricating
oil; e.g., a heavy-body oil is thick and viscous and a light-body oil is
thin and fluid. Long
e. The load-carrying part of a truck or scraper. Nichols, 1
f. The fatty, inflammable property that makes a coal combustible; e.g.,
bituminous coal has morebody than anthracite. AGI




boggildite

A fluoride, Sr2 Na2 Al2 (PO4 )F9 , from
the Greenland cryolite deposit. Spencer, 5




boghead cannel

Cannel coal rich in algal remains. See also:torbanite
Tomkeieff




boghead cannel shale

A coaly shale rich in fatty or waxy algae. AGI




boghead coal

a. A variety of bituminous or subbituminous coal resembling cannel coal in
appearance and behavior during combustion. It is characterized by a high
percentage of algal remains and volatile matter. Upon distillation it
gives exceptionally high yields of tar and oil. See also:cannel coal;
torbanite; kerosine shale.
b. A nonbanded coal with the translucent attritus consisting predominately
of algae, and having less than 5% anthraxylon. AGI




boghedite

See:torbanite




bogie

a. A rail truck or trolley of low height, used for carrying timber or
machine parts underground, or for conveying the dirt hoppit from a sinking
pit to the dirt heap. It may also be used as a wagon spotter.
See also:timber trolley
b. A weighted truck run foremost or next to the rope in a train or trip.
c. A two-axle driving unit in a truck. Also called tandem drive unit;
tandem. Nichols, 1
d. Also spelled bogey; bogy.
e. York. A small truck or trolley upon which a bucket is carried from the
shaft to the spoil bank.




bog iron

a. A general term for a soft, spongy, and porous deposit of impure hydrous
iron oxides formed in bogs, marshes, swamps, peat mosses, and shallow
lakes by precipitation from iron-bearing waters and by the oxidizing
action of algae, iron bacteria, or the atmosphere; a bog ore composed
principally of limonite that is commonly impregnated with plant debris,
clay, and clastic material. It is a poor-quality iron ore, in tubular,
pisolitic, nodular, concretionary, or thinly layered bodies, or in
irregular aggregates, in level sandy soils, and esp. abundant in the
glaciated northern regions of North America and Europe (Scandinavia).
Syn:limnite; morass ore; meadow ore; marsh ore; lake ore; swamp ore.
CF:goethite
b. A term commonly applied to a loose, porous, earthy form of "limonite"
occurring in wet ground. Syn:bog ore




bog iron ore

a. Loose, porous form of limonite occurring in wet ground, often mixed
with vegetable matter, Fe2 O3 .nH2 O .
Pryor, 3
b. A deposit of hydrated iron oxides found in swamps and peat mosses.
See also:iron ore; lake ore. CF:limnite; limonite. Syn:marsh ore;
meadow ore. Schieferdecker




bog lime

See:marl




bog manganese

a. See:earthy manganese; wad. Fay
b. A bog ore consisting chiefly of hydrous manganese oxides; specif. wad
formed in bogs or marshes by the action of minute plants.




bog-mine ore

See:bog ore




bog mine ore

See:bog ore




bog muck

A vernacular name for peat. Tomkeieff




bog oak

Oak immersed in peat bogs, semifossilized and blackened to resemble ebony
by iron from the water combining with the tannin of the oak. CMD




bog ore

a. A spongy variety of hydrated oxide of iron and limonite. Found in
layers and lumps on level sandy soils that have been covered with swamp or
bog. Includes bog iron ore, bog manganese ore, and bog lime, a calcareous
deposit of similar origin. See also:brown iron ore
b. A poorly stratified accumulation of earthy metallic-mineral substances,
mainly oxyhydroxides, formed in bogs, marshes, swamps, and other low-lying
moist places, by direct chemical precipitation from surface or
near-surface percolating waters; specif. "bog iron" and "bog manganese".
CF:lake ore




bog peat

Peat consisting mainly of mosses. Francis, 2




Bohemian garnet

Yellowish-red gem variety of the garnet pyrope; occurs very commonly in
the Mittelgebirge, Czech Republic. See also:pyrope




Bohemian ruby

A jeweler's name for rose quartz when cut as a gem. Fay




boehmite

An orthorhombic mineral, aluminum oxyhydroxide [gamma -AlO(OH)]; grayish,
brownish, or reddish, in some bauxites and laterites; an ore of aluminum,
dimorphous with diaspore. Also spelled boehmite.




bohr magneton

The net magnetic moment arising from electron spins. Van Vlack


boiler burner unit

A boiler designed esp. for gas or oil and sold integrally with the burner.
Strock, 2




boiler circulating pump

A pump, usually of the single-stage, single-entry, overhung type, that
must have low suction loss and high-temperature features since it draws
water directly from the boiler drums at high saturation pressure and
temperature. Sinclair, 4




boiling furnace

A water-jacketed reverberatory furnace for decarbonizing iron by a process
in which the carbonic oxide escapes with an appearance of boiling.
Standard, 2




boiling point

a. The temperature at which a liquid begins to boil or to be converted
into vapor by bubbles forming within its mass. It varies with pressure.
Standard, 2
b. The temperature at which a cooling gas becomes a liquid.
Hurlbut




boilum

Hard calcareous or siliceous nodules of irregular shape, found in the
shales and underclays of the Coal Measures. See also:boylom
Arkell




bolar

See:bole




bole

Any of several varieties of compact earthy clay (impure halloysite),
usually red, yellow, or brown because of the presence of iron oxide, and
consisting essentially of hydrous silicates of aluminum or less often of
magnesium. It is a waxy decomposition product of basaltic rocks, having
the variable composition of lateritic clays. Syn:bolar




boleite

A deep blue pseudoisometric hydrous oxychloride of lead, copper, and
silver from Boleo, Lower California. A tetragonal form of percylite.
Fay




Boliden gravimeter

An electrical stable gravimeter with a moving system suspended on a pair
of bowed springs. The moving system carries electrical condenser plates at
each end, one to measure the position of the moving system, the other to
apply a balancing force to bring the system to a fixed position.
Syn:Lindblad-Malmquist gravimeter




Bolognan stone

See:Bologna stone




Bologna spar

See:Bologna stone




Bologna stone

A nodular, concretionary, or round variety of barite, composed of
radiating fibers; phosphorescent when calcined with charcoal.
Syn:Bolognian stone; Bolognan stone; Bologna spar.




bolognian stone

See:Bologna stone




bolson

a. A term applied in the desert regions of the Southwestern United States
to an extensive flat alluvium-floored basin or depression, into which
drainage from the surrounding mountains flows toward a playa or central
depression; a basin with internal drainage. Syn:playa basin
AGI
b. A temporary lake, usually saline, formed in a bolson. AGI
c. Mex. A pocket of ore. Etymol: Sp., bolson, large purse.




Bolsover experiment

Applied to a method of working by single panels. Single 100-yd (91-m)
panels are advanced, leaving 100-yd-wide coal pillars between them. The
pillars are then worked on the retreat after the advancing faces have
reached a limit line. Nelson




bolt

A rod used in roof bolting. See also:slot-and-wedge bolt;
wedge-and-sleeve bolt. Nelson




bolthole

S. Staff. A short narrow opening made to connect the main workings with
the airhead or ventilating drift of a coal mine. Also called bolt.




bolt-hole brush

A special round brush used to remove porcelain enamel bisque from in and
around small openings in the ware. See also:brush




bolting

Separation of particles of different sizes by means of vibrating sieves.
Bennett




bolting silk

a. In oceanography, a silk cloth of very fine and regular mesh, used in
the construction of tow nets for the smaller members of the surface fauna.
CTD
b. Also used to cover a lap for polishing rock and mineral specimens for
microscopic examination.
?
@H ¦J }ÓÆ DICTIONARY TERMS:Bolton's reagent An etching reagent for cast iron t
[\B]Bolton's reagent[\N]




boltwoodite

A monoclinic mineral, HK(UO2 )SiO4 .1-1/2H2 O ;
analogous to sklodowskite, having potassium in place of magnesium;
radioactive; yellow.


bolus alba

See:kaolin




bomb

a. A more or less rounded mass of lava from a few inches to several feet
in diameter, generally vesicular, at least inside, thrown from the throat
of a volcano during an explosive eruption.
b. An ellipsoidal, discoidal, or irregularly rounded mass of lava ejected
at a high temperature during a volcanic eruption. Bombs range upwards in
size from the largest lapilli. They are characterized by a well-defined
crust and are often cellular or even hollow internally. Holmes, 2
c. A missile containing an explosive, as dynamite.
d. A heavy-walled reaction vessel or autoclave. Used to carry out
reactions at high pressure and high temperature. Hurlbut




bomb calorimeter

A strong steel vessel used for determining the heat produced during
combustion; used, for example, for determining the calorific value of a
fuel. Nelson




bonanza

a. A rich body of ore or a rich part of a deposit; a mine is in bonanza
when it is operating profitably. Also, discontinuous locally rich ore
deposits, esp. epithermal ones. Etymol: Sp., prosperity, success.
AGI
b. In miners' phrase, good luck, or a body of rich ore.
c. Part of a precious mineral deposit that is esp. rich.
Bateman, 2




bonattite

A monoclinic mineral, CuSO4 .3H2 O ; blue; partly dehydrated
from chalcanthite.




bond and lease

An agreement between a mine owner and tributor that gives the latter the
option of buying the mine before the lease expires. Nelson




Bond and Wang theory

A theory of crushing and grinding; the energy (h) required for crushing
varies inversely as the modulus of elasticity (E) and specific gravity
(S), and directly as the square of the compressive strength (C) and as the
approximate reduction ration (n). The energy in horsepower hours required
to crush a short ton of material is given by the following equation, in
which all quantities are in feet per second units: h = [0.001748C (super
2) / SE] [(n + 2) (n - 1) / n]. The theory is due to F. C. Bond and J. T.
Wang. Dodd




Bondaroy's yellow

An antimony yellow developed by Fourgeroux de Bondaroy in 1766: 12 parts
white lead; 3 parts potassium antimonate; 1 part alum; 1 part sal
ammoniac. Dodd




bond clay

A clay that, because of its plasticity, serves to bond relatively
nonplastic materials in the fabrication of ceramic or other molded
products (green bond). Also, a clay that, on firing to furnace or
vitrification temperature, bonds adjacent ceramic materials that vitrify
at a still higher temperature (fired bond). AGI




bonded refractories

Refractories in which the constituents are held together by a suitable
bonding material, as distinguished from fused refractories.
Henderson




bonder

a. A brick that is half as wide again as a standard square (rectangular or
arch); such bricks are sometimes used to begin or end a course of bonded
brickwork. Dodd
b. In mining, one who welds copper connections in place between the joints
of track rails, used for trolley locomotives, to complete the electrical
circuit between the sections of rails. Syn:bondman




bondman

See:bonder




Bond's third theory

In crushing, the total work useful in breakage that has been applied to a
stated weight of homogeneous broken material is invariably proportioned to
the square root of the diameter of the product particles.
Syn:work index




bone

a. A hard coallike substance high in noncombustible mineral matter; often
found above or below, or in partings between, layers of relatively pure
coal. Hess
b. In the anthracite-coal trade, a carbonaceous shale containing approx.
40% to 60% of noncombustible materials. Syn:bone coal; bony coal.
Hess
c. A tough, fine-grained, gray, white, or reddish quartz. Hess
d. A layer of hard, impure coal which sometimes grades uniformly into the
adjacent softer coal and sometimes is sharply separated from it. Bone is
usually a mixture of clay shale particles with the coal, the clay
particles being well distributed. Kentucky




bone ash

The white porous residue containing chiefly tribasic calcium phosphate
from bones calcined in air and used esp. in making cupels, pottery, and
glass and in cleaning jewelry; also, synthetic tribasic calcium phosphate
used similarly. Webster 3rd




bone bed

Applied to strata or layers that contain innumerable fragments of fossil
bones, scales, teeth, coprolites, and other organic remains. Fay




bone coal

a. Coal with a high ash content, almost rock. See also:bone
Syn:true middlings
b. Coal that has a high ash content. It is hard and compact.
Syn:bony coal
c. Argillaceous partings in coal, sometimes called slate. AGI




bone phosphate

The calcium phosphate of bones and of phosphatic rocks, such as found in
North Carolina; so called in commerce. See also:phosphorite
Standard, 2




bone phosphate of lime

Tricalcium phosphate, Ca3 (PO4 )2 . The phosphate
content of phosphorite may be expressed as percentage of bone phosphate of
lime. Abbrev: BPL. AGI




bone turquoise

See:odontolite




bonnet

a. A covering over a mine cage, which serves as a roof to shield it from
objects falling down the shaft, thereby protecting the riders.
Syn:cage cover
b. A cap piece for an upright timber. Zern
c. The metal casing of a miner's flame safety lamp, with openings at the
top and a hook for carrying the lamp. The bonnet protects the inner gauze
from damage and from the impact of high-velocity air.
See also:safety lamp
d. Syn:air dome
e. The cap over the end of a pipe. Strock, 1


bony

Coal containing slaty material in its composition. Korson




bony coal

See:bone




bonze

Undressed or untreated lead ore. Nelson




boobey

Som. A box holding 6 to 8 hundredweight of coal in which waste rock is
sent to the surface. Fay




book clay

Clay deposited in thin, leaflike laminae. Syn:leaf clay




booked mica

Lumps of mica in which laminae have not been separated into thin sheets.
Pryor, 3




book mica

Crystals of crude mica obtained from a mine in various shapes and sizes.
Also called book. Syn:mine-run mica




book structure

The alternation of ore with gangue, usually quartz, in parallel sheets.
CF:ribbon




boom

a. A spar or beam projecting out over the drill floor from the tripod or
derrick, by means of which heavy drill tools and equipment may be moved
and safely handled. Long
b. A long, adjustable steel arm on a drill jumbo on which drifter or other
types of pneumatic drills are mounted. Long
c. A cantilevered or overhanging member or structure that supports or
contains the component parts of a conveyor. It may be fixed, hinged, or
pivoted.
d. A pipe fixed across the last supports in a tunnel face to anchor the
tail sheave of a scraper loader installation. Nelson
e. In a revolving shovel, a beam hinged to the deck front, supported by
cables. Nichols, 1
f. Any beam attached to lifting or excavating equipment.
See also:dragline
g. Any heavy beam that is hinged at one end and carries a weight-lifting
device at the other. Nichols, 1




boom cat

See:stripping-shovel operator




boom conveyor

Any type of conveyor mounted on a boom.




boom ditch

a. The ditch from the dam used in booming.
b. A slight channel cut down a declivity into which is let a sudden head
of water to cut to the bedrock and prospect from the apex of any
underlying lode.




boomer

a. In placer mining, an automatic gate in a dam that holds the water until
the reservoir is filled, then opens automatically and allows the escape of
such a volume of water that the soil and upper gravel of the placer are
washed away. When the reservoir is emptied the gate closes and the
operation is repeated. On a smaller scale it may be used to furnish water
periodically for sluicing. Syn:automatic dam; flop gate. Hess
b. A sonar transducer, used in the exploration of bottom substrata.
Hy
c. Originally, an oilfield worker who migrated from one boom field to
another; now, commonly, a member of a drill crew who works one job a short
time, quits, and moves on to another locality to seek employment. Also
called drifter. Long
d. A combination ratchet and lever device used to tighten a chain or line
about a loaded truck or wagon to hold the load in place. Long




boomerang sediment corer

This free-instrument-type device can be dropped over the side of a moving
ship, where it will sink rapidly to the ocean floor, take a core of
sediment, release ballast, and automatically return to the surface for
retrieval. Hunt




booming

The accumulation and sudden discharge of a quantity of water (in placer
mining, where water is scarce). In California, the contrivances for
collecting and discharging water are termed "self-shooters," an idea
suggested by the sudden and violent manner in which the water makes its
escape. In booming, snowmelt or water from small or ephemeral streams is
collected behind a dam with a discharge gate. Placer ore is placed below
the dam and when the water is released, the ore is washed through sluice
boxes, ground sluices, etc., in one large surge. The dam discharge gate is
closed to again begin collecting water for the next cycle. Syn:hushing




boom man

In bituminous coal mining, one who manipulates the controls of a loading
boom (conveyor) to regulate the height of the loading end of a boom, thus
controlling the flow of coal from shaking screens or picking tables into
railroad cars at the tipple. Also called boom operator; loader headman.
DOT




boort

See:bort




boose

a. Eng. Lead ore that separates easily from its matrix and does not have
to be buddled, Durham, Yorkshire, and Derbyshire. Hooson defines it as
veinstuff and ore mixed. Syn:booze; bowse. Arkell
b. Derb. Gangue rock mixed with ore. See also:bouse




booster

An explosive of special character used in small quantities to improve the
performance of another explosive, the latter forming the major portion of
the charge. Nelson




booster conveyor

Any type of powered conveyor used to regain elevation lost in gravity
roller or wheel conveyor lines. Syn:humper




booster drive

An auxiliary drive at an intermediate point along a conveyor.


booster fan

A fan installed in an underground opening. A booster fan can be used as
the main mine fan but is more commonly used to improve or augment the
ventilation in a segment of the mine. Booster fans are illegal in U.S.
coal mines but are used in metal mines and coal mines in other countries.
Hartman, 2




booster pump

a. A pump used to increase the pressure of fluids, such as to increase the
pressure of water delivered to a drill when the source pressure is too low
to be used for drilling operations. Long
b. A pump that operates in the discharge line of another pump, either to
increase pressure or to restore pressure lost by friction in the line or
by lift. Nichols, 1




booster station

In long-distance pumping of liquids or mineral slurries, an intermediate
pump station. Pryor, 3




boot

a. A projecting portion of a reinforced concrete beam, acting as a corbel
to support the facing material, such as brick or stone; the lower end of a
bucket elevator. Hammond
b. A leather or tin joint connecting the blast main with the tuyere or
nozzle in a bloomery.
c. A suspended enclosure in the nose of a tank protecting a portion of the
surface and serving as a gathering opening. ASTM
d. The bottom of a bucket elevator, which receives feed for delivery into
an elevating bucket. Pryor, 3




boothite

A monoclinic mineral, CuSO4 .7H2 O ; melanterite group; of a
lighter blue than chalcanthite, from which it differs in its larger
proportion of water.




booting

The ejection of balled drill cuttings from the collar in long, tubelike
masses. Long




bootleg

a. The part of a drilled blasthole that remains when the force of the
explosion does not break the rock completely to the bottom of the hole.
See also:socket
b. See:trespass




bootlegger

One engaged in coal bootlegging. Applies to the worker in bootleg holes as
well as the worker who cleans the coal in a small, impermanent breaker,
and the trucker who conveys the coal to market. Bootleggers call
themselves independent miners. Korson




bootlegging

The mining and/or selling of coal produced from coal owned by others and
without permission or knowledge of the owner.




booze

See:boose




boracite

An orthorhombic mineral, 8[Mg6 B14 O26 Cl2 ] ;
isometric above 265 degrees C in hard, glassy, cubic and octahedral
crystals; strongly pyroelectric; in evaporites, a source of boron.




Borascu

Borate ore. Bennett




borate

A salt or ester of boric acid; a compound containing the radical BO (super
3+)3 . CF:nitrate; carbonate. AGI




borax

A monoclinic mineral, 4[Na2 B4 O5 (OH)4 .8H
2 O] ; soft; deposited by evaporation from alkaline
lakes, playas, hot springs, and as surface efflorescence or crystals
embedded in lacustrine mud. A source of boron. Syn:tincal
See also:octahedral borax




borax bead

In blowpipe analysis, a drop of borax that when fused with a small
quantity of a metallic oxide will show the characteristic color of the
element; e.g., a blue borax bead indicates the presence of cobalt.
Standard, 2




borax bead test

A chemical test to disclose the presence of certain metals in a sample. A
clear glassy bead of borax fused in a wire loop will react chemically with
the salts of certain metals and yield colors that help to identify the
metal; e.g., manganese compounds produce a violet bead, cobalt produces a
deep blue, etc. See also:blowpiping




bord

a. Newc. A passage or breast, driven up the slope of the coal from the
gangway, and hence across the grain of the coal. A bord 4 yd (3.7 m) or
more wide is called a wide bord, and one less than 4 yd in width is called
a narrow bord. Also spelled board.
b. A side gallery parallel with the main road or drift.
Standard, 2
c. A road with solid coal sides. Mason
d. A narrow coal drivage in the pillar-and-stall method of working.
Nelson
e. A joint in a coal seam. See also:cleat
f. Eng. A road driven at right angles to the main cleavage planes of the
coal. SMRB




bord-and-pillar

A method of working coal seams. First bords are driven, leaving supporting
pillars of coal between. Next, cross drives connect the bords, leaving
supporting coal as rectangular pillars. Finally, the pillars are mined
(extracted, won, robbed) and the roof is allowed to cave in. The bordroom
is the space from which bord coal has been removed. Syn:bord-and-wall;
stoop-and-room. See also:breast-and-pillar; stret;
Warwickshire method. Pryor, 3




bord-and-pillar method

A system of mining in which the distinguishing feature is the winning of
less than 50% coal on the first working. It is more an extension of the
development work than mining. The second working is similar in principle
to top slicing. The remainder of the coal is won by a retreating system,
the cover being caved after each unit has been worked. The term
bord-and-pillar is not used to any great extent in American mining
literature, but has a place in English literature. Various names have been
applied to this method, such as checkerboard system, Brown panel system,
following up the whole with the broken, Lancashire bord-and-pillar system,
modified room-and-pillar working, narrow working, North Staffordshire
method, rearer method of working inclined seams, rock-chute mining, room
system, room system with caving, Warwickshire method of working contiguous
seams, wide or square work, and pillar-and-breast. Fay




bord-and-pillar working

N. of Eng. A system of mining in which interlacing roadways are driven at
right angles into the seam, leaving small square or rectangular pillars of
coal of from 30 to 50 yd (27 to 46 m) side length, which are then wholly
or partly extracted by a small group. Syn:tub-and-stall; bord-and-wall.
See also:room-and-pillar




bord-and-wall

See:bord-and-pillar; bord-and-pillar working.


bord cleat

Eng. The main cleavage planes or joints in a coalbed. SMRB




bord course

Aust. A direction at right angles to the main cleat or facing; i.e., the
length of a bord.




bord drivage

A coal drivage in the pillar-and-stall method of working. Nelson




border facies

The marginal portion of an igneous intrusion, which differs in texture and
composition from the main body of the intrusion, possibly because of more
rapid cooling or assimilation of material from the country rock.
AGI




bord gate

a. A main gate leading and at right angles to a bord face. TIME
b. York. A heading driven generally to the rise, out of which stalls are
opened and worked.




bordroom

a. A heading driven parallel to the natural joints. Fay
b. The space excavated in driving a bord. Used in connection with the
ridding of the fallen stone in old bords when driving roads across them in
pillar working; thus, "ridding across the old bordroom." Zern
c. Eng. The width across an old bord. Fay




bordroom man

A repairer who cleans and erects supports in old workings in the
bord-and-pillar method of coal mining. Nelson




bords and longwork

York. A system of working coal. First, the main levels are started on both
sides of the shaft and carried toward the boundary. Second, the bord gates
are worked in pairs to the rise and continued as far as the boundary, or
to within a short distance of a range of upper levels and other bord
gates. Lastly, the whole of the pillars and remaining coal are worked out
downhill to within a few yards of the levels, and ultimately, all the coal
between the levels is removed. Fay




bordways

Eng. The direction of a place or a face being taken at right angles to the
main cleavage planes of a seam. SMRB




bordways course

The direction at right angles to the main cleavage planes. In some mining
districts it is termed "on face." Zern




bore

a. A tunnel, esp. while being excavated.
b. A circular hole made by boring. Long




borehole

a. A hole with a drill, auger, or other tools for exploring strata in
search of minerals, for water supply, for blasting purposes, for proving
the position of old workings and faults, and for releasing accumulations
of gas or water.
b. A circular hole made by boring; esp. a deep hole of small diameter,
such as an oil well or a water well. Also called well bore.
See also:hole




borehole bottom charge

Explosives loaded in the hole bottom at a weight or density in excess of
the main charge in order to fragment difficult to break rock or to break
an excessive toe burden.




borehole cable

Cable designed for vertical suspension in a borehole or shaft and used for
power circuits in the mines. (A borehole cable in mining may also be a
cable containing signal, telephone, or control circuits.)




borehole casing

A steel pipe lining used in a borehole, particularly when passing through
loose, running ground. Flush-jointed casing that is smooth inside and
outside may be either screwed or welded. Nelson




borehole deformation gage

A device for measuring the change in diameter of a hole.




borehole log

A record, made by the driller or geologist, of the rocks penetrated in the
borehole. In the laboratory, a more detailed log is prepared giving
particulars relating to lithology, paleontology, water analysis, etc.
See also:electric log; well log. Nelson




borehole logging

The determination of the physical, electrical, and radioactive properties
of the rocks traversed by a borehole. BS, 9




borehole mining

The extraction of minerals in the liquid or gaseous state from the Earth's
crust by means of boreholes and suction pumps. Boreholes are used for
mining petroleum, and for the extraction of liquid solutions of salt,
sulfur, etc. See also:well




borehole pressure

The pressure that the hot gases of detonation exert on the borehole wall.
It is primarily a function of the density of the explosive and the heat of
explosion. Syn:gas pressure




borehole pump

a. Any pump that can be suspended in a borehole; usually a centrifugal
pump suspended in a borehole by its pipe range and driven by a shaft
inside the pipe. BS, 10
b. A centrifugal pump, electrically driven, and designed in the form of a
vertical narrow chamber. It may be used to provide water, for dewatering
purposes, or for borehole mining. See also:sinking pump
submersible pump. Nelson


borehole samples

The samples of the rocks obtained during boring. The diamond and shot
drill yield cores, while percussive drills yield sludge and chippings,
which are examined to determine the nature of the rocks passed through.
Borehole samples may also be required during site investigations.
See also:exploratory drilling; soil core. Nelson




borehole sealing

The complete filling of a borehole with cement to prevent the entry of
water into mine workings. Nelson




borehole spacing

The distance between boreholes drilled for exploration or sampling
purposes. With bedded minerals, the holes may be positioned at the
intersection points of coordinates or at the corners of equilateral
triangles with sides from 30 to 200 m apart. The spacing is closer with
patchy deposits. With metallic ores following belts across country, the
holes are spaced along lines crossing the orebody in order to yield cross
sections of the ore at definite intervals. In the case of known and
semiproved coalfields, boreholes at 1/2- to 1-km intervals may suffice.
Nelson




borehole survey

a. The process of determining the course of, and the target point reached
by, a borehole, using one of several different azimuth and dip recording
apparatuses small enough to be lowered into a borehole; also, the record
of the information thereby obtained. Also called drillhole survey;
directional survey. Long
b. The process of determining the mineralogical, structural, or physical
characteristics of the formations penetrated by a borehole using
geophysical logging apparatus small enough to be lowered into a borehole;
also, the record of the information thereby obtained. Long
c. See:well log




borehole surveying

Instrumental tests to determine the amount and direction of deflection of
a borehole from vertical and horizontal planes. The instrument is lowered
into the hole and tested at intervals of depth. The data obtained may be
used to construct a scale model showing the actual course taken by the
hole. Nelson




bore meal

a. Eng. Mud or fine cuttings from a borehole.
b. In rock drilling, the sludge from a borehole. Pryor, 3




borer

A tool such as a drill used for boring.




bore rod

Term used primarily by soil and foundation testing engineers for the
equipment customarily called a drill rod by drillers and miners.
Long




borides

A group of special ceramic materials. Typical properties are great
hardness and mechanical strength, high melting point, low electrical
resistivity, and high thermal conductivity; impact resistance is low, but
thermal-shock resistance is generally good. Dodd




boring

a. The cutting or drilling of a hole for blasting, water infusion,
exploration, or water or combustible gases drainage.
See also:percussive boring; rotary boring.
b. The drilling of deep holes for the exploitation or exploration of
oilfields. The term "drilling" is used similarly in connection with
metalliferous deposits. CTD




boring bar

a. A rod, made in various lengths, usually with a single chisel cutting
edge, for hand drilling in rock. The blows are given by a sledge hammer.
Nelson
b. A revolving or stationary bar carrying one or more cutters or drills
for boring. Fay




boring log

See:drill log




borings

Used by the soil and foundation testing profession as a syn. for boreholes
and/or the materials removed from a borehole. CF:cuttings; sample.
Long




bornite

An isometric mineral, 1[Cu5 FeS4 ] ; metallic; brownish
bronze tarnishing to iridescent blue and purple; brittle; massive; in
hypogene and contact metamorphic deposits and mafic rocks; a valuable
source of copper. Syn:erubescite; variegated copper ore; peacock ore;
horseflesh ore; poikilit; purple copper ore; variegated ore.




boron

The element is not found free in nature, but occurs as orthoboric acid in
volcanic spring waters and as borates in borax and colemanite. The most
important source of boron is the mineral rasorite, also known as kernite.
Symbol, B. Amorphous boron is used in pyrotechnic flares and in rockets as
an igniter; the most important compound, boric acid or boracic acid, is
used as an antiseptic; borax is used as a cleansing flux in welding and as
a water softener. The isotope boron-10 is used in nuclear reactors; the
nitride has lubricating properties similar to those of graphite; and the
hydrides have been studied for use as rocket fuels.
Handbook of Chemistry and Physics, 3




boronatrocalcite

See:ulexite




boron carbide

Probably not a true compound, but instead a solution of varying amounts of
carbon in a slightly distorted boron lattice; symbol, BC; black; hexagonal
rhombohedral crystals; ranking next to diamond in hardness, 9.3 on the
Mohs scale; and melting point, 2,350 degrees C. Used in powder form as an
abrasive and in molded form as an abrasion resister.
Syn:tetraboron carbide




boronitrocalcite

A former name for ulexite.




boron nitride

White; symbol, BN; hexagonal rhombohedral, crystals or powder; the powder
has a Mohs hardness of 2; sublimes at about 3,000 degrees C; anisotropic;
some properties vary according to the method of preparation and the
crystal form. Used as a refractory; a high-temperature lubricant, as in
glass molds; in furnace insulation; and in molten-metal pump parts.
CCD, 2; Handbook of Chemistry and Physics, 2




boron phosphate

Symbol, BPO; sp gr, 2.81; vaporizes at 1,400 degrees C; related
structurally to high cristobalite. It has been used as a constituent of a
ceramic body that fires to a translucent porcelain at 1,000 degrees C.
Dodd




boron phosphide

Symbol, BP; melting point, greater than 2,000 degrees C, but readily
oxidizes, which limits its potential use. Dodd


boron silicides

See:silicon borides




borrow material

Soil or sediment removed from a site for use in construction, such as
sandy sediment dredged and pumped to restore an eroded beach, or clay
taken to build a levee or dike. Army Corps of Eng.




borrow pit

a. The source of material taken from some location near an embankment
where there is insufficient excavated material nearby on the job to form
the embankment. Borrow-pit excavation is therefore a special
classification, usually bid upon as a special item in contracts. It
frequently involves the cost of land or a royalty for material taken from
the land where the borrow pit is located; it also often requires the
construction of a suitable road to the pit. This type of excavation
therefore usually runs higher in cost than ordinary excavation.
Hess
b. An excavated area where borrow has been obtained. AGI




bort

a. Diamond material unsuitable for gems because of its shape, size, or
color and because of flaws or inclusions. It also occurs in finely
crystalline aggregates and is usually crushed into finer material.
Syn:boart; bortz; boort; boartz; borts; bowr. See also:shot bort
b. Inferior, coarsely crystalline diamonds, many of which contain black
carbon or other minerals; used for core drilling, cutting, and polishing
hard materials.
c. Formerly used to mean the Brazilian carbonado or black diamond.
Hess
d. Industrial diamond. ASM, 1
e. Very hard, flawed or discolored diamonds used in drilling and glass
cutting. Gordon
f. S. Afr. Rounded forms of diamond with rough exterior and radiated or
confused crystalline structure, but hardness equal to that of diamond.
Beerman
g. Originally the term was used as a name for all crystalline diamonds not
usable as gems; later it was used to designate those diamonds not usable
as gems or toolstones. Currently the term is applied to low-grade
industrial diamonds suitable only for use in a fragmented form.
h. A granular to very finely crystalline aggregate consisting of
imperfectly crystallized diamonds or of fragments produced in cutting
diamonds. It often occurs as spherical forms, with no distinct cleavage,
and having a radial fibrous structure. AGI
i. A diamond of the lowest quality, so flawed, imperfectly crystallized,
or off-color that it is suitable only for crushing into abrasive powders
for industrial purposes (as for saws and drill bits); an industrial
diamond. Originally, any crystalline diamond (and later, any diamond) not
usable as a gem. AGI
j. A term formerly used as a syn. of carbonado. CF:ballas
Syn:magnetic bort




bort bit

See:diamond bit




borts

See:bort




bort-set bit

See:diamond bit




bortz

See:bort




bosh

a. The section of a blast furnace extending upward from the tuyeres to the
plane of maximum diameter. ASM, 1
b. A lining of quartz that builds up during the smelting of copper ores
and thus decreases the diameter of the furnace at the tuyeres.
ASM, 1
c. A trough in which bloomery tools (or in copper smelting, hot ingots)
are cooled. Fay




bosh jacket

A water jacket used for cooling the walls of a shaft furnace. Fay




bosh tank

A water tank that receives newly cast copper shapes for rapid cooling.
Pryor, 3




boss

a. Arkansas. A coal mine employee not under the jurisdiction of the
miner's union. Fay
b. A proturberant and often dome-shaped mass of igneous rock congealed
beneath the surface of the Earth and laid bare by erosion.
Webster 3rd
c. An igneous intrusion that is less than 40 mi2 (104 km (super
2) ) in surface exposure and is roughly circular in plan. CF:stock
AGI




bossing

Scot. The holing or undercutting of a thick seam, as of limestone, the
height of the undercutting being sufficient for a person to work in.




Boss process

Modification of the pan-amalgamation process; ore slurry flows
continuously through a series of pans and settling tanks. Bennett




bostonite

A light-colored hypabyssal rock, characterized by bostonitic texture and
composed chiefly of alkali feldspar; a fine-grained trachyte with few or
no mafic components. The name is derived from Boston, MA, for no clear
reason. Not recommended usage. AGI




bostonitic

Said of the texture of bostonite, in which microlites of rough irregular
feldspar tend to form clusters of divergent laths within a trachytoid
groundmass. AGI




bostrichites

An early name for prehnite.




botallackite

A monoclinic mineral, Cu2 Cl(OH)3 ; trimorphous with
atacamite and paratacamite.




botanical anomaly

A local increase above the normal variation in the chemical composition,
distribution, ecological assemblage, or morphology of plants, indicating
the possible presence of an ore deposit or anthropomorphic contamination.
See also:geobotanical prospecting




botanical prospecting

Prospecting in which differences in plant growth or plant family serve as
a clue to the presence of metals beneath barren rock or a covering of sand
and gravel. Pearl




botryogen

A monoclinic mineral, MgFe3+ (SO4 )2 (OH).7H (sub
2) O ; reniform, botryoidal, or globular; hyacinth-red to orange; in
secondary sulfate deposits capping sulfide ore deposits.
Syn:red iron vitriol


botryoid

A form in the shape of a bunch of grapes. Syn:clusterite
botryoidal.




botryoidal

Having the form of a bunch of grapes. Said of minerals, e.g., hematite
with a surface of spherical shapes; also said of a crystalline aggregate
in which the spherical shapes are composed of radiating crystals.
CF:colloform; colloid minerals; reniform.




botryolite

A radiated, columnar variety of datolite with a botryoidal surface.
Standard, 2




bottom

a. The floor or footwall of an underground mine.
b. The landing of a shaft or slope.
c. See:gutter
d. To complete a borehole.
e. To construct the bottom of or for; said specif. of underdraining a
level. Standard, 2
f. To strike bedrock or clay when sinking a shaft. Standard, 2
g. The landing at the bottom of the shaft or slope. Fay
h. The lowest point of mining operations. Fay
i. To underrun (as a gold deposit that is to be worked by the hydraulic
method) with a level for drainage. Webster 3rd
j. Surface in a borehole parallel to the face of a drill bit. Long
k. A mass of impure metal formed below the matte, in matting metal ores.
l. The footwall of a metalliferous deposit. Nelson
m. Barren bedrock. Nelson
n. The rock formation below the alluvium on which the gold or tin wash
dirt is met. Gordon
o. In gemstones, the pavilion.
p. Pennsylvania. The stratum, rock, or floor on which a coal seam lies.
Standard, 2
q. To break the material and throw it clear from the bottom or toe of the
borehole.
r. To place a drill bit in contact with the bottom of a borehole.
s. Surface in a borehole parallel to the face of a drill bit.
t. In metal-melting furnaces, this is usually the hearth or crucible.
See also:bottoming




bottom bed

Eng. Universally applied to the lowest bed in a quarry. Also used in
Southeast England for the basal bed of the Tertiary, whether Thanet sand
or Reading beds, resting on an eroded surface of the Chalk.




bottom belt conveyor

A belt conveyor that carries the coal or ore on the lower strand; often
used where height is limited. Nelson




bottom benching

The method by which the bench is removed from below as with a power
shovel. See also:benching




bottom bounce

Technique by which sonar impulses are reflected off the ocean bottom one
or more times before reaching the target. Also refers to diving.
Hy




bottom break

The break or crack that separates a block of stone from a quarry floor.
Hess




bottom canch

In leveling an underground roadway, a part taken out below a bed.
See also:canch




bottom coal

Coal below the undercut; it may or may not be removed.




bottom cut

a. A machine cut made in the bottom or floor of a seam before shot firing.
See also:cutting horizon; middle cut; top cut. Nelson
b. A drill hole pattern. See also:drag cut
c. In drilling and blasting a tunnel, the lower of two converging lines of
horizontally spaced holes. Upper line is draw cut. When blasted
simultaneously, a wedge of rock is removed. Pryor, 3




bottom cutter

A dinter; a coal cutter for making floor cuts. Nelson




bottom diameter

The diameter of a circle tangent to the seating curve at the bottom of the
tooth gap of a roller chain sprocket. Equal to the pitch diameter minus
the chain-roller diameter. Jackson, 1




bottom-discharge bucket conveyor

A conveyor for carrying bulk materials in a horizontal path consisting of
an endless chain to which roller-supported, cam-operated, bottom-discharge
conveyor buckets are attached continuously.




bottom-discharge conveyor bucket

A vessel generally rectangular or square in plan and having a bottom
consisting of an undercut gate.




bottom-dump car

See:mine car




bottom-dump scraper

A carrying scraper that dumps or ejects its load over the cutting edge.
Nichols, 1




bottom-dump semitrailers

Suitable for transporting free-flowing materials over a reasonably level
haul route that permits a high travel speed. They can be used where the
maximum flotation of a large single tire is required and where dumping in
windrows over a wide area is practical. See also:bottom dump truck
Carson, 1




bottom dump truck

A trailer or semitrailer that dumps bulk material by opening doors in the
floor of the body. Also called dump wagon.
See also:bottom-dump semitrailers




bottomed

a. A completed borehole, or the point at which drilling operations in a
borehole are discontinued. Long
b. Said of shafts and slopes on being driven to completion when reaching
base of coal seam.


bottom-emptying skip

A skip equipped with a bottom discharge gate. Sinclair, 5




bottom equipment

a. The tools or equipment attached to the lower end of a drill string and
normally used at or near the bottom of a borehole. Also, the nondrilling
equipment placed and operated at or near the bottom of a borehole, such as
a pump unit or strainer. Long
b. Mine equipment used solely for work at the mine bottom, such as rotary
dump and switch motor (if used to spot cars in rotary dump).




bottom filler

A worker who fills a barrow with ore, coke, or stone, weighs it, and then
places it on the cage or elevator to be hoisted to the top of the furnace.
Fay




bottom gate

The gate road at the lower end of an inclined coal face.
See also:main gate; tailgate; top gate. Nelson




bottom heading

a. Method of excavating tunnels, drifts, or other mine openings. The
bottom heading, which may be either driven in successive stages or holed
through, is subsequently enlarged by excavating the top section.
Fraenkel
b. Overhand bench.




bottom hole

A point at, or near, the bottom of a borehole. Long




bottom-hole pressure

a. The load, expressed in pounds or tons, applied to a bit or other
cutting tool while drilling. Long
b. The pressure, expressed in pounds per square inch, produced at the
bottom of a borehole by the weight of the column of circulation or other
liquid in a borehole. Long
c. The pressure, expressed in pounds per square inch, exerted by gas or
liquids ejected from the rocks at or near the bottom of a drill hole.
Long
d. Pressure measured in a well opposite the producing formation. If the
well is flowing, the flowing bottom-hole pressure will be obtained; if the
well is not producing and has not been producing for a sufficient time,
the pressure will be the fully built-up, or static, bottom-hole pressure.
CF:ground pressure




bottom-hole temperature

The temperature of the fluid at or near the bottom of a borehole;
significantly lower than the temperature of the formation if borehole
fluids have been circulated recently or are being produced with expansion
into the well bore. Long




bottoming

The downward pinching-out or termination of an orebody, either
structurally or by economic grade. See also:bottom




bottom lift

a. The lowest or deepest lift or level of a mine. Zern
b. The deepest columns of a pump. Zern
c. The deepest lift of a mining pump, or the lowest pump. Fay




bottom loading belt

A bottom belt conveyor. Nelson




bottom maker

A laborer who relines bottoms of ingot soaking pits with coke dust to
retard formation of oxide scale on hot ingots. DOT




bottom pillar

A large block of solid coal left unworked around the shaft.
See also:shaft pillar




bottom-pour ingot assembly

One comprising hot tops, wood blocks, ingot mold, mold stool, lateral
outlet bricks, lateral bricks, king brick, fountain bricks, funnel brick,
and suitable metal supporting devices.




bottom-pour ladle

A ladle poured through a refractory nozzle in the bottom.




bottom rock

See:bedrock




bottoms

a. Used in connection with the Orford process for separating nickel and
copper as sulfides. When the mixed sulfides are fused with sodium sulfide,
the nickel sulfide separates to the bottom. See also:tile copper
CTD
b. The material drawn off from the bottom of a tower or still. Any residue
accumulating in the bottom of a process vessel.




bottom sample

A sample obtained by collecting a portion of material on the bottom of a
container or pipeline. Bennett




bottom sampler

One of various types of apparatus capable of piercing the sea bottom and
retaining a sample of the deposit when brought to the surface. CTD




bottom sheets

The steel plates forming the bottom of an oil still or a steam boiler.
Hess




bottom subsidence

See:subsidence


bott plug

A clay ball used for stopping the taphole in a cupola furnace.
Mersereau, 2




bott stick

A long stick used for inserting the bott plug into the taphole to stop the
flow of metal. Mersereau, 2




boudin

a. One of a series of elongate, sausage-shaped segments occurring in
boudinage structure, either separate or joined by pinched connections, and
having barrel-shaped cross sections. AGI
b. A term applied loosely, without regard to shape or origin, to any
tectonic inclusion. Etymol: French, bag; blood sausage. AGI




boudinage

A structure common in strongly deformed sedimentary and metamorphic rocks,
in which an original continuous competent layer or bed between less
competent layers has been stretched, thinned, and broken at regular
intervals into bodies resembling boudins or sausages, elongated parallel
to the fold axes. See also:pull-apart structure




Bouguer anomaly

A gravity anomaly calculated after corrections for latitude, elevation,
and terrain. Pron: boo-gay. See also:anomaly; Bouguer correction.
AGI




Bouguer correction

A correction made to gravity data for the attraction of the rock between
the station and the datum elevation (commonly sea level); or, if the
station is below the datum elevation, for the rock missing between station
and datum. The Bouguer correction is 0.01276 ph mgal/ft, or 0.04185 ph
mgal/m, where p is the specific gravity of the intervening rock and h is
the difference in elevation between station and datum.
See also:Bouguer anomaly




Bouguer gravity

Gravity values after latitude, elevation, and Bouguer corrections have
been applied. Used in the gravitational method of geophysical prospecting.
Nelson




Bouguer reduction

The correction made in a gravity survey to take account of the altitude of
the station and the rock between the station and sea level. AGI




boulangerite

A monoclinic mineral, Pb5 Sb4 S11 ; metallic;
bluish-gray; massive.




boulder

a. A detached rock mass larger than a cobble, having a diameter greater
than 10 in (25.4 cm) or 8 phi units, or about the size of a volleyball,
being somewhat rounded or otherwise distinctively shaped by abrasion in
the course of transport; the largest rock fragment recognized by
sedimentologists. In Great Britain, the limiting size of 8 in (20.3 cm)
has been used. AGI
b. See:boulder stone
c. A general term for any rock that is too heavy to be lifted readily by
hand. Also spelled bowlder. AGI




boulder blasting

a. The breaking down of large stones at quarries by small explosive
charges. See also:secondary blasting
b. Secondary blasting of rocks too big to be moved conveniently in the
mine's transport system. Pryor, 3




boulder buster

An explosive used to break rock fragments by blockholing or mudcapping
methods. Long




boulder clay

a. The stiff, hard, and usually unstratified clay of the drift or glacial
period that contains boulders scattered through it. Also called till;
hardpan; drift clay; drift. See also:till; moraine. Fay
b. Glacial drift that has not been subjected to the sorting action of
water and therefore contains mixed particles ranging from boulders to clay
sizes. ASCE




boulder flat

A level tract covered with boulders. AGI




boulder gravel

An unconsolidated deposit consisting mainly of boulders. AGI




boulder motion

A surface quarry worked only in detached masses of rock overlying the
solid rock; sometimes contracted to motion. Standard, 2




boulder quarry

A quarry in which the joints are numerous and irregular, so that the stone
has been broken naturally into comparatively small blocks. A local term
applied to certain marble quarries in the region of Knoxville, TN, where
erosion has formed many large cavities and cracks, between which the rock
stands up as pinnacles. The cavities are now filled with clay. Fay




boulder stone

An obsolete term for any large rock mass lying on the surface of the
ground or embedded in the soil, differing from the country rock of the
region, such as an erratic. Syn:boulder




boule

A fused mass of synthetic material up to 5 cm long, pear or carrot-shaped,
particularly as produced by the Verneuil or Crochralshi processes in the
production of synthetic sapphire, ruby, spinel, or rutile. Etymol: Fr.
"ball." Syn:birne




boulet

A small ovoid; an egg-shaped briquette. BS, 5




bounce

a. A sudden spalling off of the sides of ribs and pillars due to excessive
pressure; a bump. Zern
b. The rapid up-and-down reciprocating motion induced in a drill string by
rod vibration, drill string wrap-up, excessive volume or pressure of
circulation media, or the running of a bit on and over small, loose
materials on the bottom of a drill hole. Long


bounce cast

Casts of short grooves (up to 5 cm) widest and deepest in middle and
fading out at both ends; presumably formed by objects grazing against
bottom and rebounding. See also:impact cast
Pettijohn, 1




bound

Corn. An area taken up for tin mining; a tin bound. Standard, 2




boundary

a. A line between areas of the Earth's surface occupied by rocks or
formations of different type and age; esp. used in connection with
geologic mapping; also, a line between two formations or cartographic
units on a geologic map.
b. The limit, border, or termination of a coal or mineral take; a line
along which workings must stop in the vicinity of a fault or old
waterlogged workings. Also called march. Nelson




boundary fault

A major fault with a considerable displacement. A number of collieries and
coalfields are limited along one side by such a fault. Nelson




boundary films

Films of one constituent of an alloy surrounding the crystals of another
constituent. CTD




boundary map

A map created for the purpose of delineating a boundary line and the
adjacent territory. AGI




boundary pillar

A pillar left in mines between adjoining properties.




bound gravel

A hard, lenticular, cemented mass of sand and gravel occurring in the
region of the water table; it is often mistaken for bedrock. AGI




Bourdon tube

Pressure gage, made from elliptical curved tube, which straightens
somewhat under pressure, and is made to move a measuring needle over a
dial. Pryor, 3




bournonite

An orthorhombic mineral, 4[PbCuSbS3 ] ; shows wheel-shaped twin
crystals; a source of lead, copper, and antimony. Syn:wheel ore;
cogwheel ore; endellinite; endellionite; berthonite.




bouse

N. of Eng. Ore mixed with veinstone; second-class ore that must undergo
further preparation before going to the smelter. See also:boose




bouse team

N. of Eng. The place where bouse is deposited outside a mine, ready to be
dressed or prepared for the smelter.




bout

Derb. A method of measuring lead ore. Nelson




bouteillenstein

A peculiar green and very pure glass, found as rolled pebbles. Also called
bottle stone; pseudochrysolite--the latter from its resemblance to
olivine. It is not solely a rock, as it may be prehistoric slag or glass.
See also:moldavite




boutgate

a. Scot. A road by which the miners can reach the surface.
b. A passage around a shaft at a landing.
c. A traveling road from one seam to another.




bouton

a. Scot. A mass of roof consisting of stone or shale.
b. Scot. A projecting stone in a shaft or underground road.




bowenite

a. A hard, compact, greenish-white to yellowish-green serpentine once
thought to be nephrite jade; translucent; massive, fine-grained; consists
of a dense feltlike aggregate of colorless antigorite fibers with patches
of magnesite, flakes of talc, and grains of chromite.
Syn:bowenite jade
b. N.Z. Serpentine rock (serpentinite). Syn:tangiwai; tangiwaite;
tangawaite.




bowenite jade

See:bowenite




Bowen's reaction series

See:reaction series




bowk

a. S. Staff. A small wooden box in which iron ore is hauled underground.
Syn:hudge
b. Aust. An iron bucket used for raising rock, etc., while sinking.
Syn:hudge
the coal beneath.
d. Bucket; kibble; hoppit, as used in sinking. Mason
e. A large iron barrel used for men's tools and debris when sinking a
shaft. CTD
f. The noise made by the escape of gas under pressure.




bowl

a. The bucket or body of a carrying scraper. Nichols, 1
b. The moldboard or blade of a dozer. Nichols, 1
c. Stationary part of a Symons crusher, which surrounds the cone (the
grating member). Pryor, 3
d. See:spider


bowl classifier

A hydraulic classifier similar to a thickener, but differs in that the
current carries the fine material into the overflow; used to make
separations at very fine particle size.




bowlder

See:boulder




bowlingite

See:saponite




bowl scraper

A steel bowl hung within a fabricated steel frame, running on four or two
wheels. Its bottom edge digs into the ground, the bowl being filled as it
is drawn forward by a tractor; soil is ejected at the dump by a tailgate,
moved by wire ropes or hydraulically. Towed scrapers transport soil, in
addition to spreading and leveling it. See also:wheel scraper
Hammond




bowr

See:bort




bowse

See:boose




box

a. A unit in a sluice for washing gravel; a sluicebox.
Syn:box condenser
b. A dump body. Nichols, 1
c. To place core samples in a lidded, traylike, partitioned container for
safekeeping after they have been removed from the core barrel; also, the
container in which core samples are placed after they have been removed
from a core barrel. Also called corebox; core tray. Long
d. To drill boreholes at the four corners of a square area at equal
distances from a centrally located and already completed borehole.
Long




box barrow

A large wheelbarrow with upright sides. Webster 2nd




box bell

See:bell screw




box canyon

a. A narrow gorge or canyon containing a stream following a zigzag course,
characterized by high, steep rock walls and typically closed upstream with
a similar wall, giving the impression as viewed from its bottom of being
surrounded or boxed in by almost-vertical walls. AGI
b. A steep-walled canyon heading against a cliff; a dead-end canyon.
Syn:cajon




boxcar loader

a. Any of several types of conveyors adapted by portable or hinged
mounting for use in loading bulk materials into boxcars. Some types
operate at high speeds and throw the materials to the ends of the car.
See also:idler disk
b. In anthracite and bituminous coal mining, one who loads coal into
railroad boxcars by mechanical shovel or conveyor loader.
Syn:thrower belt; car loader; loader engineer; loader runner.
See also:portable conveyor




box check

A ventilation control consisting of a stopping or a curtain with a hole,
through which a conveyor can pass. The box check serves as a ventilation
regulator in a belt haulage entry. See also:boxes; conveyor airlock.
MSHA, 1




box condenser

See:box




box cut

The initial cut driven in a property, where no open side exists; this
results in a highwall on both sides of the cut. Austin




box-cut method

A method of opencast mining of coal where the dip of the seam is
relatively steep. A boxlike excavation is made to the dip, or at an angle
to it, and the coal seam is worked to the right and left.
See also:strike working




box-cut spoil

That spoil created from the initial excavation of a pit or pits which is
placed upon the surface of adjacent lands. The term does not include spoil
from subsequent excavations, which is placed in previously excavated pits.




boxes

a. Pennsylvania. Wooden partitions for conducting the ventilation from
place to place. See also:box check
b. More or less hollow cuboidal limonitic concretions. Arkell
c. Eng. Pebbles of hard brown sandstone at the base of the Red and
Coralline Crags in East Anglia, containing remains of a fossil; so called
by the Suffolk phosphate diggers. Arkell




box filling

The use of metal trays, instead of shovels, for hand-filling coal into
trams. The collier scooped the lumpy coal into the box and discarded the
small material, which had little market value. The use of a box was
compulsory at many collieries until several decades ago.
See also:fork-filled; loading pan. Nelson




box groove

A closed groove between two rolls, formed by a collar on one roll and
fitting between collars on another. Fay




box heading

A heading driven through very loose ground with close timbering.
Nelson




boxing

A method of securing shafts solely by slabs and wooden pegs. Zern


box loader

In the quarry industry, one who loads broken rock into a large box, placed
on a small truck running on a narrow gauge track, to be hoisted out of the
quarry pit. Syn:grouter; rock loader. DOT




box scraper

See:scraper




box sluice

An open wooden channel or flume for conveying placer sand. The gold or
heavy minerals settle at the bottom. The method is cleaner and requires
less water than ground sluicing. Nelson




box tap

See:bell tap




box timbering

Use of rectangular close frame for lining shafts or drives.
See also:plank timbering




boxwork

A network of intersecting blades or plates of limonite or other iron
oxide, deposited in cavities and along fracture planes from which sulfides
have been dissolved by processes associated with the oxidation and
leaching of sulfide ores, esp. porphyry copper deposits. AGI




boydite

Local name for probertite. English




boylom

Staff. A bluish iron ore. See also:boilum




Boylston's reagent

A 5% solution of nitric acid in absolute ethyl or methyl alcohol, used for
the general etching of normal carbon steels. Syn:nital




BPL

Bone phosphate of lime. AGI




BQ

Letter name specifying the dimensions of bits, core barrels, and drill
rods in the B-size and Q-group wireline diamond drilling system having a
core diameter of 36.5 mm and a hole diameter of 60 mm. Cumming, 2




brace

A platform or landing at the top of a shaft. The upper brace is the
platform built in the headgear above the shaft collar. Nelson




brace head

A cross handle attached at the top of a column of drill rods by means of
which the rods and attached bit are turned after each drop in
chop-and-wash operations while sinking a borehole through overburden. Also
called brace key. Long




brachy axis

The shorter lateral axis in the crystals of the orthorhombic, monoclinic,
and triclinic systems. Webster 3rd




brachypinacoid

a. A pinacoid parallel to the vertical axis and the brachydiagonal.
Standard, 2
b. The pinacoid 010 intersecting the brachy-axis in orthorhombic and
triclinic systems (obsolete). CF:pinacoid




brachytypous

In crystallography, comparatively short. Standard, 2




bracing

a. Diagonal or horizontal members used to prevent swaying of structures,
i.e., conveyor-supporting structures.
b. Eng. See also:lacing




brackebuschite

A monoclinic mineral, Pb2 (Mn,Fe)(VO4 )2 .H2 O.




Brackelsberg process

A process by which fine ores are moistened with water to which a binding
medium is added, and the wet mass, without any heating, is rotated in a
drum until it forms into spherical lumps of varying size. The moisture is
then dried out by evaporation, and the product remains in the form of
hard, very porous balls of ore, which are of great reducibility as
compared with sintered ore or briquettes. Osborne




bracket

A platform over a shaft entrance. Standard, 2




brackish water

Water in which salinity values range from approx. 0.50 to 17.00 parts per
thousand. Hy


Bradford breaker

A machine that combines coal crushing and screening. It consists of a
revolving cylindrical screen 8 to 14 ft (2.4 to 4.3 m) in diameter and 13
to 22 ft (4.0 to 6.7 m) in length. It breaks the coal by gravity impact.
On reaching the desired size, the coal is discharged through the plates.
It can deal with run-of-mine coal up to 12 in (30.5 cm) at a rate of 500
to 600 st/h (454 to 544 t/h), to give a product size of below 1-1/2 in
(3.8 cm); other sizes can be produced, depending on the screen plates
used. See also:screen




bradleyite

A monoclinic mineral, Na3 Mg(PO4 )(CO3 ) ; in
veryfine grains in saline oil shale in Wyoming.




bradyseism

A long-continued, extremely slow vertical instability of the crust, as in
the volcanic district west of Naples, Italy, where the Phlegraean
bradyseism has involved up-and-down movements between 6 m below sea level
and 6 m above over more than 2,000 yr (Casertano). Etymol: Greek "bradys"
(slow) + "seismos" (earthquake). AGI




brae

Insufficiently charred wood, as in charcoal burning. Standard, 2




Bragg angle

The angle, theta , at which X-rays diffract in crystalline materials. It
satisfies the relationship n lambda = 2 d sin theta , where d is the
distance between diffraction planes of atomic particles in a crystal
structure, lambda is the wavelength of the X-rays, and n is the order of
diffraction when a crystal is placed in an X-ray beam.




Bragg indices

The index numbers assigned to a diffracted X-ray beam. They have the same
values as Miller indices but are written without closures. Diffraction
order may be factored into Bragg indices, e.g., 111, 222, 333... represent
n = 1, 2, 3... for diffraction from atomic planes parallel to 111 .
CF:Miller indices




braggite

A tetragonal mineral (Pt,Pd,Ni)S : steel gray, minute grains in
concentrates from the Bushveld norite of the Transvaal, South Africa. A
source of platinum and palladium.




braided stream

A stream that divides into an interlacing or tangled network of several
small branching and reuniting shallow channels separated from each other
by branch islands or channel bars, resembling in plan the strands of a
complex braid. Such an anastomosing stream is generally believed to
indicate an inability to carry all of its load, such as an overloaded and
aggrading stream flowing in a wide channel on a flood plain. AGI




brake

a. A device (as a block or band applied to the rim of a wheel) to arrest
the motion of a vehicle, a machine, or other mechanism and usually
employing some form of friction. Webster 3rd
b. A device, either hand- or power-operated, for applying resistance to
the drum or pulley and thus controlling the movement of mine cars or
cages. A common form is a brakeshoe, lined with friction material, which
is applied to the surface of a wheel or drum, and thus retards or even
stops its movement. See also:winder brake
Nelson
c. Eng. A stout, wooden lever to which boring rods are attached. It is
worked by one or more people.
d. N. Staff. To lower trams on dips by means of a wheel and rope.




brakedrum

A rotating cylinder with a machined inner or outer surface upon which a
brake band or brakeshoe presses. Nichols, 1




brake incline

a. An incline in which the full trucks descend by gravity and pull up the
empty ones. See also:gravity haulage
b. Gravity plane. Pryor, 3




brakeman

a. Person who attends to a brake or brakes, as on a railroad car.
Standard, 2
b. Eng. The person in charge of a winding (hoisting) engine for a mine.
"Brakeman" is usually used in the United States; "brakesman" is the
British usage. The person in charge of hoisting engines, esp. in the
United States, is usually called a hoisting engineer. Fay
c. In mining, a laborer who rides on trains or trips of cars hauled by
locomotive or hoisting cable or chain, and assists in their transportation
to surface or shaft bottom for hoisting; operates or throws switches;
couples and uncouples cars, or attaches and detaches cars to and from the
cable; opens and closes ventilation doors in mines; directs movement of
the train by signaling motorman. May be designated according to type of
hauling machine, such as dinkey operator helper. Also called brake holder,
car rider, conductor, dukey rider, gang rider, motorman helper, nipper,
patcher, rider, rope conductor, rope rider, set rider, snapper, tailend
rider, trailer, train conductor, trainman, transfer car helper, trip
rider, tub rider. Syn:conductor




brake sieve

A jigger operated by a hand lever. Fay




brake wheel

a. A hand wheel for operating a brake, as on a vehicle.
Webster 2nd
b. A wheel or pulley on which a friction brake acts. Webster 2nd
c. A heavy wheel provided with cams for controlling the movement of a
triphammer. Webster 2nd




braking distance

Tbe distance the haulage unit (i.e., train) will travel after the
application of the brakes, depending on the speed, the weight of
locomotive and train, and the gradient. Sinclair, 5




brammallite

A micaceous mineral differing from illite because it contains soda in
excess of potash. Found in crevices in coal measure shales from Llandebie,
South Wales. Syn:sodium illite




brances

See:brasses




branch

a. An underground road or heading driven in coal measures; also, a roadway
turned from a level, etc. Syn:branch hole
b. A small vein departing from the main lode. CF:main hole




branch fault

A minor fault that branches from a larger fault. Stokes




branch headings

Headings that are turned off the main level at intervals for development
purposes. They may proceed to the rise or dip and are adopted in longwall
and pillar methods of working. See also:opening out




branch hole

See:branch


branchite

A variety of hydrocarbon found in lignite. According to Hintz it is
identical with hartite. Tomkeieff




brandisite

Clintonite found as monoclinic hexagonal-shaped prisms in metamorphosed
limestone.




brannerite

A monoclinic mineral, (U,Ca,Y,Ce)(Ti,Fe)2 O6 ; radioactive;
commonly metamict; in placers of the Stanley Basin, UT.




brashings

Brittle shale (the coal miner's "slate") interbedded with thin coalbeds;
also, the roof of the Pittsburgh coal in western Maryland.
See also:rashings




brasque

A paste made by mixing powdered charcoal, coal, or coke with clay,
molasses, tar, or other suitable substance. Used for lining hearths,
crucibles, etc. Syn:steep




brasqued crucible

A crucible lined with charcoal or lampblack, and used for the reduction of
oxides of metals to the metallic state. The crucible is prepared by
ramming it full of lampblack or charcoal, and then excavating a portion of
its contents and polishing the lining with a burnisher. Fay




brass balls

Nodular pyrite. Fay




brasses

Mineral impurities in coal, of yellow metallic appearance, consisting
mainly of iron sulfides. Syn:brances; brassyn. BS, 4




brassfounder's disease

A disease affecting the general system, characterized by chronic poisoning
from inhalation of metallic fumes, with symptoms like those of malarial
fever. Standard, 2




brass furnace

One of two kinds of furnaces for the making and founding of brass: (1) a
reverberatory furnace for producing large quantities of the alloy, or (2)
a crucible furnace for producing small quantities. Fay




brass ore

a. An early name for a mixture of sphalerite and chalcopyrite.
Hess
b. An old name for aurichalcite.




brassyn

See:brasses




brassy top

Aust. The top part of the Greta coal seam, in which there are large
quantities of sulfide of iron.




brattice

a. Ventilating partition, usually of coated fabric, used to direct air to
various faces to remove gas and dust.
b. A board or plank lining, or other partition, in any mine passage to
confine the air and force it into the working places. Its object is to
keep the intake air from finding its way by a short route into the return
airway. Temporary brattices are often made of cloth. Also spelled
braddish; brettice; brettis; brattish. See also:brattice cloth
c. An airtight partition in a mine shaft to separate intake from return
air. See also:screen
d. Used as jumpers for removing gas from a roof cavity. Nelson
e. To provide with a brattice for separation or support; often used with
up. Syn:brattice up




brattice cloth

a. Fire-resistant fabric, usually coated, used to erect a brattice.
b. A heavy canvas, often covered with some waterproofing material, for
temporarily forcing the air into the face of a breast or heading; also
used in place of doors on gangways; then known as "sheets."
Syn:brettice cloth




brattice man

In mining, a worker who builds doors, stoppings and curtains (ventilation
walls or partitions in active workplaces) of burlap, canvas, and wood.
Also called airman; braddisher; braddish man; canvasman; doorman;
ventilation man. DOT




brattice road

A road through the goaf supported by chocks or timber packs.




brattice sheeting

A curtain or screen of flexible material used to direct or control the
flow of ventilating air. See also:brattice cloth; sheets. BS, 8




brattice up

See:brattice




brattice worker

See:airman




brattish

See:brattice


braunite

A tetragonal mineral, Mn2+ Mn3+6 SiO12 ;
brittle; may contain appreciable iron.




braunkohle

Ger. See:brown coal




bravaisite

A former name for a micaceous clay later shown to be a mixture of
montmorillonite and illite.




Bravais lattice

One of 14 ways points may be arrayed periodically in space such that each
point is in an identical point environment. Every crystal structure has
associated with it a Bravais lattice. Syn:space lattice;
crystal lattice. CF:direct lattice; space group.




Bravais law

See:Bravais rule




Bravais-Miller indices

See:Miller-Bravais indices




Bravais rule

The most prominent faces of a crystal are those parallel to internal
planes having the greatest density of lattice points. Syn:Bravais law




bravoite

A nickeloan variety of pyrite.




braze

To solder with brass or other hard alloys. Nichols, 1




brazilianite

A monoclinic mineral, NaAl3 (PO4 )2 (OH)4 ;
yellow-green; also spelled brasilianite, brasilianita.




Brazilian pebble

A colorless transparent quartz, such as is used for optical purposes.
Fay




Brazilian test

A method for the determination of the tensile strength of rock, concrete,
ceramic, or other material by applying a load vertically at the highest
point of a test cylinder or disk (the axis of which is horizontal), which
is itself supported on a horizontal plane. The method was first used in
Brazil for testing concrete rollers on which an old church was being moved
to a new site. Dodd




brazilite

a. A mixture of baddeleyite, zircon, and altered zircon.
b. A fibrous variety of baddeleyite.
c. An oil shale.




Brazil twin

A type of twin found in quartz in which the two crystalline individuals
are of opposite kinds, one being right-handed, the other left-handed, with
a face of the trigonal prism of the second order as twinning plane. Since
one is not derivable from the other by any rotation, there is no twinning
axis. Hess




brazing

a. Joining metals by flowing a thin layer (capillary thickness) of
nonferrous filler metal into the space between them. Bonding results from
the intimate contact produced by the dissolution of a small amount of base
metal in the molten filler metal, without fusion of the base metal.
Sometimes the filler metal is put in place as a thin solid sheet or as a
clad layer, and the composite is heated as in furnace brazing.
ASM, 1
b. In joining metals, the term "brazing" is used where the temperature
exceeds some arbitrary value, such as 800 degrees F (427 degrees C); the
term "soldering" is used for temperatures lower than the arbitrary value.
ASM, 1




breach

a. An opening made by breaking down a portion of a solid body, as a wall,
a dike, or a riverbank; a break; a gap.
b. The face of a level or drift.
c. A large cave hole caused by undermining.




breached anticline

An anticline whose crest has been deeply eroded, so that it is flanked by
inward-facing erosional scarps. CF:bald-headed anticline




breaching

The breaking through of a bar. Schieferdecker




breadth

N. Staff. A set of coal pillars formed by rearer workings. Nelson




break

a. A plane of discontinuity in the coal seam such as a slip, fracture,
joint, or cleat. The surfaces are in contact or slightly separated.
See also:break detector
b. A fracture or crack in the roof beds as a result of mining operations.
See also:breakes; induced fracture. Nelson
c. To separate core from solid rock at the bottom of a borehole by a
tensional pull applied to the drill string. Long
d. In mineral processing, optimum mesh of grind (m.o.g.), the practical
size range to which ore is reduced before concentration. Not synonymous
with liberation mesh. Pryor, 3
e. In drilling, to unscrew, as rods, casing, drill pipe, etc. Long




breakage

a. Voluntary or involuntary division of a solid. BS, 5
b. Small material produced by involuntary breakage during mechanical
handling or processing. BS, 5


breakage clause

Eng. A clause inserted in some mining leases providing for an abatement of
royalty or allowance on weight for certain weight of small coal or
breakage sent out in every ton of large coal, for example, 120 lb (54.5
kg) in every collier's ton of 2,640 lb (1,200 kg).




breakage of coal

See:degradation




breakaway chain

A chain that holds a tractor and a towed unit together if the regular
fastening opens or breaks. Syn:safety chain




breakback

The fractures caused by the shattering of a solid rock ledge back of the
drill holes in which the charge is placed. Fay




break detector

A scraper capable of detecting breaks in a shothole. See also:break;
stemmer. Nelson




breakdown

Of an emulsion, the reunion of the finely dispersed particles and their
separation from the medium in which they form an emulsion. Syn:hoedown
CTD




breakdown voltage

The voltage at which an insulator or dielectric ruptures; or the voltage
at which ionization and conduction begin in a gas or vapor. Hunt




breaker capacity

The ability of a switch, in a particular situation, to clear safely the
heaviest fault current that can flow; it depends upon the amount of power
available in the system, size of cables, transformers, etc.
CF:breaking capacity




breaker props

Props, or props and cribs, set to break the roof off at a prearranged line
during retreat mining, or when blasting down roof.




breakers

The row of drill holes above the mining holes in a tunnel face.
Stauffer




breaker zone

See:surf zone




breakes

Eng. Fissures in old coal workings. See also:break




break-even point

a. Production level at which total cost equals revenue. Pryor, 3
b. Value or selling price of ore, metal, or mined material that just
balances total cost of operations; conversely, maximum unit costs above
which there is no profit at given market values.




break-in

To start drilling operations with a new bit by rotating the bit slowly
under a light load for a short time before full speed and load are applied
to the bit. Long




breaking

Size reduction of large particles. Also called cracking. BS, 5




breaking capacity

The capacity of a switch, circuit breaker, or other similar device to
break an electric circuit under certain specified conditions.
CF:breaker capacity




breaking-down rolls

A rolling mill unit used for breaking-down operations; a rolling mill used
for reducing sectional dimensions, mainly thickness--of ingots, billets,
and other rough, semifinished products--as a preliminary step to
subsequent rolling operations. Henderson




breaking ground

a. The breaking and loosening of rock as a preparatory step to its loading
and removal. See also:excavation
b. Attrition of an ore deposit by hand, explosive, or mechanical breaking
methods to reduce it to pieces of ore suitable for transport and
treatment. Pryor, 3




breaking in

N. of Eng. See:hewing




breaking-in shot

a. The first borehole fired in "blasting off the solid" to provide a space
into which material from subsequent shots may be thrown. Also called
opening shot; buster shot. Fay
b. In blasting a solid face, the first hole or group of holes of a round
to be fired simultaneously. See also:burn cut




breaking lag

As applied to an electric blasting cap, the time elapsing between the
bridge wire receiving the firing impulse and the breaking of the circuit.
Fraenkel


breaking point

In rock crushers, a deliberate weak link that yields if excessive strain
is developed. May be a scarfed toggle, weak cap bolts on a pitman, a
shearpin in drive, or a clutch designed to fail at a given load.
Pryor, 3




breaking prop

Arkansas. One of a row of props of sufficient strength to cause the rock
above the coal to break and so limit the area of top brought down by a
brushing shot.




breakings

Inferior ores arranged ready for crushing. Nelson




breaking stress

See:fracture stress




break in lode

A fault.




break line

a. The line in which the roof of a coal mine is expected to break.
b. The line of complete extraction of coal.
c. A line roughly following the rear edges of the pillars that are being
drawn or mined. See also:rib line




break-making

Providing a crack indication by striking small slits in the longitudinal
direction of a row of drill holes in quarries.




breakout

a. To pull drill rods or casings from a borehole and unscrew them at
points where they are joined by threaded couplings to form lengths that
can be stacked in the drill tripod or derrick. Long
b. An accidental flow of metal through a hole in a furnace lining.




breakrow

A row of timbers erected for the purpose of breaking the roof in pillar
mining. Hess




breakthrough

a. A passage cut through a pillar to allow the ventilating current to pass
from one room to another. Larger than a doghole. Also called room
crosscut. Syn:cut-through; crosscut.
b. The point at which a drill bit leaves the rock and enters either a
natural or a constructed opening. Long
c. An opening made, either accidentally or deliberately, between two
underground workings. Long
d. In an ion-exchange column used in leaching, the arrival of traces of
uranium in the final column during the loading (adsorption) cycle.
Pryor, 3
e. See:stenton




break thrust

A thrust fault that cuts across one limb of a fold. AGI




breakup

a. Eng. An excavation commenced from the bottom of a tunnel heading and
carried upward, so as to form two interior working faces.
b. Mid. To cut away and remove the floor of an entry or other opening.




breakup value

On exhaustion of an ore deposit or cessation of an exploitation, the value
of its onsite buildings, equipment, stockpiles, untouched remnants of ore
concentrates, etc.; in foundations of plant; and any other assets still
having value apart from their original use. Pryor, 3




breakwater

An offshore structure (such as a mole, wall, or jetty) that, by breaking
the force of the waves, protects a harbor, anchorage, beach, or shore
area. AGI




breast

a. In a coal mine, a chamber driven in the seam from the gangway, for the
extraction of coal; the face of a working.
b. In Italy, a stall in a steep seam from 12 to 18 yd (11 to 16.5 m) wide.
The stalls are carried one above another from the lowest level to the
rise.
c. Leic. To take down or get a buttock (face) of coal end on.
d. The end, in unmined rock, of an underground excavation, sometimes
called the face; the vertical end surface of a block.
See also:before breast
e. A place where anthracite coal is mined; in the soft coal regions, it is
called a room. BCI
f. The face of a working.
g. That part of the bedplate that is back of the crossheads in engines of
the Corliss type.
h. The side of the hearth containing the taphole in a blast furnace; the
rammed material in which the taphole is installed in a cupola.




breast-and-pillar

Pennsylvania. A system of working anthracite coal by bords 10 yd (9.1 m)
in width, with narrow pillars 5 yd (4.6 m) wide between them, holed
through at certain intervals. The breasts are worked from the dip to the
rise. See also:bord-and-pillar




breast auger

An auger supported by a breastplate against a miner's body. Used for
drilling holes in soft coal. Fay




breast board

a. Planking placed between the last set of timbers and the face of a
gangway or heading which is in quicksand or loose ground.
b. The timber or boards placed horizontally across the face of an
excavation, or heading, to prevent the inflow of gravel or other loose or
flowing material. Stauffer




breast bore

Scot. A borehole put in parallel with the seam, that is made and kept in
advance of a working place for the purpose of ascertaining the position of
old works, tapping water, letting off gas, etc. Fay




breast coal

The face of the middle or main layer of coal in a composite seam.
Nelson




breast drill

A small, portable hand drill customarily used by handsetters to drill the
holes in bit blanks in which diamonds are to be set. The upper end of the
drill is provided with a plate against which the breast of the operator is
pressed to force the bit into the work. CF:brace


breaster

In tunnel blasting, holes that parallel the tunnel alignment drilled
between the cut and the perimeter holes.




breast eye

Lanc. Opening leading from a working face to the surface. Hess




breast hole

In driving a tunnel, a hole blasted after the bottom cut. Pryor, 3




breasting

a. N. Staff. A short leading stall, worked at right angles to, and forming
the face of, the main level.
b. A wide heading or level.
c. Eng. Taking ore from the face or head of a drift.
d. In drift mining, breaking down the gravel underground, and retreating
towards the crosscut from which the drifts were driven.
von Bernewitz
e. Cumb. A place driven to open out a longwall face. SMRB




breast machine

A machine used for undercutting coal in which the main frame and carriage
are held stationary by roof jacks while the cutter frame advances into the
kerf during the cutting operation. Since cuts do not exceed 44 in (1.1 m)
along the face, it is necessary to relocate the machine several times
before the entire face can be cut. Jones, 1




breastplate

A slightly curved iron plate fastened to the end of a coal auger to enable
a miner to press the auger forward using body pressure.




breast stoping

A method of stoping employed on veins where the dip is not sufficient for
the broken ore to be removed by gravity. The ore remains close to the
working face and must be loaded into cars at that point.
See also:overhand stoping




breast timber

A leaning brace from the floor of an excavation to a wall support.
Nichols, 1




breast wall

A wall designed to withstand the force of a natural bank of earth, such as
of timber used to support the face of a tunnel. Syn:jamb wall
AGI




breathing

Alternate expansion and contraction of air in breaks that allows fresh
oxygen to be drawn in and oxidation to proceed. Sinclair, 1




breathing apparatus

a. A filter self-rescuer (FSR) is a respiratory protective device that
filters ambient air of carbon monoxide, converting it to carbon dioxide.
Exhaled air is vented back to ambient. Also called a gas mask. Duration of
protection is limited, usually, by water contamination of the chemical
bed. Used for escape from underground mines in the event of a fire or
explosion. Requirement specified in 30 CFR 75.1714-2(e)(2). Apparatus must
be certified as providing at least one hour of respiratory protection.
Apparatus available in the United States are the Draeger 910 and the MSA
W-65, both certified for one hour.
b. A self-contained self-rescuer (SCSR) is a respiratory protective device
that provides breathing gas independent of the ambient atmosphere,
containing its own oxygen source. Also called an oxygen self-rescuer. Air
is exchanged between the user's lungs and a breathing bag. Oxygen consumed
by the user is replaced by the apparatus from its oxygen source, stored
either in chemical or compressed form. Carbon dioxide produced by the user
is removed by a chemical absorbent in the apparatus breathing circuit.
Duration of protection is determined by both quantity of stored oxygen and
carbon dioxide absorption capacity. SCSRs differ from rescue breathing
apparatus in that the breathing bag is not protected by a rigid cover in
order to reduce size and weight. Used for escape from underground mines in
the event of a fire or explosion. Requirement specified in 30 CFR 75.1714.
Apparatus must be certified as providing at least one hour of respiratory
protection. Apparatus available in the United States are the CSE SR-100,
the Draeger OXY K plus, the MSA Portal-Pack, the Ocenco EBA 6.5, all
certified for one hour.
c. A rescue breathing apparatus (RBA) is a respiratory protective device
that provides breathing gas independent of the ambient atmosphere,
containing its own oxygen source. Air is exchanged between the user's
lungs and a breathing bag. Oxygen consumed by the user is replaced by the
apparatus from its oxygen source, stored in compressed form in most
apparatus. Carbon dioxide produced by the user is removed by a chemical
absorbent in the apparatus breathing circuit. Duration of protection is
determined by both quantity of stored oxygen and carbon dioxide absorption
capacity. RBAs differ from self-contained self-rescuers in that the
breathing bag is protected by a rigid cover in order to prevent accidental
puncture or tear. Used for entry into underground mines after a fire or
explosion in order to reestablish the ventilation system, rescue trapped
miners, and put out fires. Requirement specified in 30 CFR 49.1. Apparatus
must be certified as providing at least two hours of respiratory
protection. Apparatus available in the United States are the Biomarine
BioPak 240 and the Draeger BG-174A, both certified for four hours.




breathing cave

a. A cave in which air is alternately blown out and sucked in at the
entrance. Schieferdecker
b. A narrow part in a passage through which air blows.
Schieferdecker




breccia

A coarse-grained clastic rock, composed of angular broken rock fragments
held together by a mineral cement or in a fine-grained matrix; it differs
from conglomerate in that the fragments have sharp edges and unworn
corners. Breccia may originate as a result of talus accumulation,
explosive igneous processes, collapse of rock material, or faulting.
Etymol: Italian, broken stones, rubble. Syn:rubblerock
brecciated. CF:conglomerate; loose ground. AGI




brecciated

Converted into, characterized by, or resembling a breccia; esp. said of a
rock structure marked by an accumulation of angular fragments, or of an
ore texture showing mineral fragments without notable rounding.
AGI




bredigite

An orthorhombic mineral, Ca7 Mg(SiO4 )4 ;
pseudohexagonal. CF:larnite




breeching

Mid. Drawing loaded trams downhill underground. Syn:britching




breese

See:breeze




breeze

a. Coke of small size; the undersize remaining after separating the
smallest size of graded coke. Also spelled breese. BS, 3
b. The dust from coke or coal. Mersereau, 2
c. An indefinite term that usually means clinker, but that may refer to
coke breeze. Taylor
d. Scot. Fine or slack coal.




breeze concrete

A concrete made of 3 parts coke breeze, 1 part sand, and 1 part portland
cement. It has poor fire-resisting qualities but it is cheap and nails can
be driven into it. Nelson




breeze oven

a. An oven for the manufacture of small coke. Fay
b. A furnace designed to consume breeze or coal dust. Fay




breithauptite

Nickel antimonide, NiSb. See also:niccolite


brenston

See:brimstone




Breton pan

Large steel mortar in which a heavy steel pestle rolls. Once used in
grinding and amalgamation of gold ores. Pryor, 3




brettice cloth

A variation of brattice cloth. See also:brattice cloth




brettis way

Derb. A road in a coal mine, supported by brattices built on each side
after the coal has been worked out. See also:brattice




breunnerite

A ferroan variety of magnesite used in the manufacture of magnesia bricks.




brewsterite

A monoclinic mineral, (Sr,Ba,Ca)Al2 Si6 O16 .5H (sub
2) O ; zeolite group.




brewsterlinite

Liquid plus vapor CO2 in cavities in minerals; e.g., quartz, topaz,
and chrysoberyl. The meniscus vanishes under the warmth of the hand.




Brewster's law

a. The index of refraction of a crystalline substance is equal to the
tangent of its angle of polarization. Pryor, 3
b. In optics, where light is reflected from a smooth, transparent,
nonconducting surface, it is plane polarized parallel to the reflecting
surface. The angle of incidence for maximum polarization is that angle
whose tangent is the index of refraction of the reflecting substance. This
angle is also called the "Brewster angle."




brick clay

An impure clay, containing iron and other ingredients. In industry the
term is applied to any clay, loam, or earth suitable for the manufacture
of bricks or coarse pottery. Syn:brick earth




brick coal

Eng. Small, dirty coal suitable for brick kilns and similar purposes.
Fay




brick earth

Earth, clay, or loam suitable for making bricks; specif. a fine-grained
brownish deposit consisting of quartz and flint sand mixed with
ferruginous clay; found on river terraces as a result of reworking by
water of windblown material, such as that overlying the gravels on certain
terraces of the Thames River in England. Syn:brick clay




brick fuel

In Wales, patent fuel. See also:briquette




bricking

The walling or casing of a shaft.




bricking curb

A curb set in a circular shaft to support the brick walling.
See also:curb




bricking scaffold

A staging or platform suspended in a sinking shaft on which masons stand
when building brick walling. Syn:walling scaffold




brick walling

A permanent support for circular shafts. On reaching the rockhead, a firm
ledge is prepared to receive the first bricking curb or ring. The curb is
fixed correctly with reference to the centerline of the shaft. The bricks
are then built upwards from the curb, the space behind being firmly packed
to the rock sides with bricks and mortar. Concrete is replacing brickwork
as a shaft lining. See also:lining; permanent shaft support.
Nelson




bridal

Staff. A contrivance used in coal mining to prevent cars from overturning
upon steep inclined planes having a rise of 1 ft in 3 ft or 4 ft (1 m in 3
m or 4 m). Hess




bride cake

A black, highly carbonaceous slickensided shale with Carbonicola shells,
in the Adwalton stone or Flockton thick coal; also, dirty smudgy coal in
the roof of the Stanley Main in the Snydale-don Pedro area.
Syn:bright cake




bridge

a. A rock fragment, cavings, or other obstruction that lodges (either
accidentally or intentionally) part way down in a drill hole (such as in
an oil well). AGI
b. Debris that plugs a borehole at a point above the bottom. Between the
underside of the bridge and the bottom of the drill hole, the borehole is
free of debris. Long
c. To deliberately plug a borehole at a point some distance above its
bottom. Long
d. To form a bridge in a drill hole. AGI
e. In a cave, a solutional remnant of rock that spans a passage from wall
to wall. AGI
f. A device to measure the resistance of a wire or other conductor forming
a part of an electric circuit.
g. A piece of timber held above the cap of a set by blocks and used to
facilitate the driving of spiling in soft or running ground.
h. Refers to the overburden used for spanning the natural gap between the
highwall and the spoil, when such is required to establish a temporary
machine surface standing area closer to the disposal area than that
provided by the virgin ground. AGI
i. In an electric blasting cap, the wire that is heated by electric
current so as to ignite the charge. Nichols, 1
j. Sometimes, the shunt connection between the cap wires.
Nichols, 1
k. A plankway or elevator used in ironworking to convey fuel or ore to the
mouth of a furnace. Webster 3rd
l. A refractory bar, or member, or fire clay placed across the surface of
the batch in a tank furnace near the working end to hold back the scum, or
gall. Mersereau, 2
m. The structure formed by the end walls of the adjacent melter and
refiner compartments of a tank and the covers spanning the gap between the
end walls. ASTM
n. See:air crossing




bridge break

The time that elapses between the application of current and the fusion of
the bridge wire when using instantaneous blasting caps. Streefkerk




bridge conveyor

A conveyor that is supported at one end by a loading unit and at the other
end in such a way as to permit changes in the position of either end
without interrupting the operation of the loading unit. NEMA, 2


bridged

A borehole plugged by debris lodged at some point above the bottom of a
hole. The hole may be bridged deliberately by introducing foreign material
into the hole or accidentally by rock fragments sloughing off the
sidewalls of the borehole. Long




bridge over

Collapse of a well bore around the drill stem. Williams




bridge the hole

Deliberate plugging of a borehole at a point some distance above the
bottom by introduction of some type of foreign material or a plug.
See also:bridge




bridge tramway

Consists of two steel bridge trusses braced together so as to form between
them a runway on which a bucket-carrying trolley runs.
Pit and Quarry




bridge wall

A low separating wall, usually made of firebrick, in a furnace.
Webster 3rd




bridgewire

A resistance wire connecting the ends of the leg wire inside an electric
detonator and which is embedded in the ignition charge of the detonator.




bridging

a. In crushing practice, the obstruction of the receiving opening by two
or more pieces wedged together, each of which could easily pass through.
Nelson
b. Formation of arches of keyed or jammed particles across the direction
of flow (of rock through apertures or of small particles through filter
pores). Pryor, 3
c. Arching of the charge across the shaft in a blast furnace or cupola.
d. Premature solidification of metal across a mold section before the
metal below or beyond solidifies. ASM, 1
e. Solidification of slag within the cupola at or just above the tuyeres.
ASM, 1
f. Welding or mechanical locking of the charge in a downfeed melting or
smelting furnace. ASM, 1
g. Closing of a section of a drill hole by loose blocks of rock or by
squeezing of plastic shale, etc.




Bridgman sampler

A mechanical device that automatically selects two samples as the ore
passes through.




bridle bar

See:bridle rod




bridle cable

An anchor cable that is at right angles to the line of pull.
Nichols, 1




bridle chain

a. One of the chains used for supporting a cage from the winding rope.
Nelson
b. One of the safety chains used to support the cage if the shackle should
break or to protect a train of cars on a slope should the shackle or
drawbar fail. Fay




bridle hitch

A connection between a bridle cable and a cable or sheave block.
Nichols, 1




bridle rod

A steel tie bar used to join the ends of two point rails to hold them to
gage in the proper position. Syn:bridle bar




brier

N. of Eng. A beam or girder fixed across a shaft top.




Briggs clinophone

An instrument used in measuring borehole deviation which transmits
electrical signals, communicating to the surface the position of a plumb
bob fitted with a needle relative to four electrodes arranged N.,S.,E.,
and W.--the needle and electrodes being immersed in the electrolyte.
Signals are matched with a similar arrangement of needle and electrodes at
the surface, and the needle then indicates the deviation and the direction
of deviation. Sinclair, 2




Briggs equalizer

This consists of a head harness, mouthpiece, and noseclip, corrugated
breathing tube, Briggs equalizing device, 120 ft (36.58 m) of reinforced
air tubes, and a strainer and spike. It has neither bellows nor rotary
blower but depends entirely on the action of the equalizer for comfortabIe
respiration. The resistance to breathing is so low that reasonably hard
work can be done by the wearer over a period of 2 h or more. The air
supply tube is attached to the waist by a strong leather body belt.
Mason




bright attritus

A field term to denote the degree of luster of attrital coal compared with
the brilliant luster of associated vitrain. CF:dull attritus
AGI




bright cake

See:bride cake




bright coal

a. A type of banded coal defined microscopically as consisting of more
than 5% of anthraxylon and less than 20% of opaque matter; banded coal in
which translucent matter predominates. Bright coal corresponds to the
microlithotypes vitrite and clarite and in part to duroclarite and
vitrinerite. CF:dull coal
b. The constituent of banded coal that is of a jet black, pitchy
appearance, more compact than dull coal, and breaking with a conchoidal
fracture when viewed macroscopically, and that in thin section always
shows preserved cell structure of woody plant tissue, either of stem,
branch, or root. Same as anthraxylon. AGI
c. A coal composed of anthraxylon and attritus, in which the translucent
cell-wall degradation matter or translucent humic matter predominates.
AGI
d. A type of banded coal containing from 100% to 81% pure bright
ingredients (vitrain, clarain, and fusain), the remainder consisting of
clarodurain and durain. AGI




bright head

a. York. A smooth parting or joint in coal; a plane of cleavage.
b. The principal cleat in coal. Arkell




brightness

The candlepower of a light source divided by the area of the source, and
expressed in candles per square inch or candles per square foot.


brightness meter

Visual-type portable photometer operated by visual comparison of
brightness. So named because it can be calibrated to indicate the
photometric brightness of the object viewed in the sighting telescope.
Roberts, 2




brights

a. Coal that reflects a large part of incident light, either in a definite
beam or by scattering. Two kinds of bright coal are distinguished:
vitrain, which reflects an incident beam in a definite direction and
consequently appears light or dark according to whether the beam is or is
not reflected into the eye; and clarain, which scatters the light and
shows a silky luster at whatever angle it is viewed. Tomkeieff
b. A commercial term for the larger sizes of bright coal. BS, 4




bright sulfur

Crude sulfur free of discoloring impurities and bright yellow in color.
USBM, 7




brimstone

A common name for sulfur. Syn:brenston




brine

a. Water saturated or strongly impregnated with common salt.
b. Sea water containing a higher concentration of dissolved salt than that
of the ordinary ocean. CF:artificial brine




brine field

A section of land under which quantities of rock salt or natural brine of
usable strength have been discovered and a well, or any number of wells,
has been bored for raising the brine. Kaufmann




Brinell hardness test

A test for determining the hardness of a material by forcing a hard steel
or carbide ball of specified diameter into it under a specified load. The
result is expressed as the Brinell hardness number, which is the value
obtained by dividing the applied load in kilograms by the surface area of
the resulting impression in square millimeters.
CF:Vickers hardness test




Brinell hardness tester

a. In heat treating, one who determines the hardness of pieces of metal by
the Brinell hardness test. Also called Brinell operator. DOT
b. The machine or instrument used to determine hardness.




brine pit

A salt well, or an opening at the mouth of a salt spring, from which water
is taken to be evaporated for making salt. AGI




brine well

A cased drill hole penetrating a salt formation through which water is
introduced and brine pumped to the surface.




bring in

Can. Develop a mine from prospect stage. Hoffman




briquette

A block of compressed coal dust, used as fuel; also, a slab or block of
artificial stone. Syn:brick fuel; coalette; eggette. Also called
boulet; carbonet. Also spelled briquet. See also:solid smokeless fuel
Standard, 2




briquetting

A process by which coke breeze, coal dust, iron ore, or any other
pulverized mineral is bound together into briquettes, under pressure, with
or without a binding agent such as asphalt, and thus made conveniently
available for further processing or for commercial markets.
Y ?p?ÜŸ g DICTIONARY TERMS:Briska detonator An aluminum tube containing a main
[\B]Briska detonator[\N]




Britannia cell

In mineral processing, a pneumatic flotation cell 7 to 9 ft (2.1 to 2.7 m)
deep. See also:southwestern cell




britching

Scot. See:breeching




British equivalent temperature

See:equivalent temperature




British thermal unit

Heat needed to raise 1 lb (0.45 kg) of water 1 degrees F (5/9 degrees C)
(equal to 252 cal or 1,054 J). Symbol, Btu. CF:heat unit
Pryor, 3




brittle material

A nonductile material that fails catastrophically under dynamic loading
conditions. Ceramics are an example of a class of brittle materials.
Hunt




brittle mica

Group of micas having brittle laminae. Chief member is chloritoid, a basic
silicate of aluminum, iron, and magnesium, Fe2+ ,Mg,Mn)2
Al4 Si2 O10 (OH)4 . See also:mica;
margarite. Pryor, 3




brittleness

a. Of minerals, proneness to fracture under low stress. A quality
affecting behavior during comminution of ore, whereby one species
fractures more readily than others in the material being crushed.
See also:toughness
b. The quality of a material that leads to crack propagation without
appreciable plastic deformation. ASM, 1




brittle silver ore

See:stephanite


broach

a. To restore the diameter of a borehole by reaming. Long
b. To break down the walls between two contiguous drill holes.
Long
c. A sharp-pointed chisel, used for rough dressing stone.
Webster 2nd
d. The perpendicular grooves machined into the bit mold in which inside
and outside gage stones are set. Long




broaching

a. Trimming or straightening a mine working.
b. A method of rock excavation employed where it is important that the
adjacent rock formation should not be shattered by explosive. A line of
closely spaced holes is drilled along the required line of breakage. The
rock between the holes is knocked out with a broach and removed with the
aid of wedges. See also:channeler
c. Removing metal stock from a workpiece with a broach. ASM, 1




broaching bit

A tool used to restore the dimensions of a borehole that has been
contracted by the swelling of the marl or clay walls; also used to break
down the intervening rock between two contiguous drill holes. A reamer.
Fay




broad coke oven

A special design of oven, used mainly for coking certain grades of coal.




broadgate

Eng. A main working.




broad lode

Where two or more mining claims longitudinally bisect or divide the apex
of a vein, the senior claim takes the entire width of the vein on its dip,
if it is in other respects so located as to give the right to pursue the
vein downward outside of the sideline. In other words, a broad lode
bisected by the division sidelines between two mining claims belongs to
the claim having the prior location. The term lode has become extensively
used in the classification of ore deposits that are not comprehended by
the definition of a vein. Such an occurrence is called a broad lode or
zone. See also:broad vein




broadside shooting

A type of refraction seismic shooting used to determine the structure
across the strike. The broadside lines are ordinarily laid out in
conjunction with the standard-type profiles that run along the strike. The
shot points and detector spreads are laid out along parallel lines, which
are generally across the strike. The distance between each line of shots
and the receiving line is chosen so that it will always be greater than
the double offset distance for the refractor being followed. Generally the
distance should be only slightly greater so that the primary refracted
event will be received as a second arrival. When this spacing is used, the
refracting point associated with the shot will be very close to that
associated with the detector, and each delay time will be approx. half the
intercept time. A single depth point (based on half the intercept time) is
then plotted midway between shot and receiver. All depth points are thus
placed along the "control lines" that are located halfway between the
shooting line and the receiving line. Dobrin




broadstone

A paving slab, so called because it is raised broad and thin from the
quarries, not more than 2 to 3 in (5.08 to 7.62 cm) thick.




broad vein

Where a broad vein apexes so that the boundary line between two claims
splits the apex, the extralateral rights go to the senior locator, who
takes the entire width of the vein on the dip; i.e., a broad lode that is
bisected by the division side line between two mining claims belongs to
the claim having the prior location. See also:broad lode




brochantite

A monoclinic mineral, Cu4 (SO4 )(OH)6 ; has one good
cleavage; occurs in the oxidation zone of copper sulfide deposits; a
source of copper. Formerly called blanchardite, kamarezite.
Syn:waringtonite




brockite

A hexagonal mineral, (Ca,Th,Ce)(PO4 ).H2 O ; rhabdophane
group.




broeggerite

A thorian variety of uraninite. Also spelled broggerite.




broggite

a. A variety of asphalt from Peru. Tomkeieff
b. A variety of anthraxolite. Crosby




broil

An old Cornish mining term referring to a collection of loose rock
fragments usually discolored by oxidation, and indicating the presence of
a mineral vein beneath the outcrop or gossan. Also spelled bryle; broyl.




broken charge

A charge of explosive in a drill hole divided into two or more parts that
are separated by stemming. Fay




broken coal

In anthracite only; coal that is small enough to pass through a 3-3/8- to
4-in (8.57- to 10.16-cm) square aperture, but too large to pass through a
2-3/4-in or 2-1/2-in (6.99-cm or 6.35-cm) mesh. Smaller than steamboat,
and larger than egg coal. See also:anthracite coal sizes




broken ground

a. A shattered rock formation or a formation crisscrossed with numerous,
closely spaced, uncemented joints and cracks. CF:loose ground; breccia.
Long
b. Rock or mineral formations fragmented by blasting with explosives, such
as the broken material in a shrinkage stope. Syn:broken rock
Long




broken rock

See:broken ground




brokens

a. Eng. The removal or extraction of pillars previously formed in bord and
pillar working. In Durham and Northumberland, the terms robbery and
robbing pillars imply incomplete extraction of the pillars. SMRB
b. Robbery.
c. Robbing pillars.




broken stone

a. A diamond that has been shattered in use, or lost a portion of its size
by cleaving. Long
b. See:crushed stone




broken working

The working away or removal of blocks or pillars of coal formed by whole
workings. See also:working the broken


bromargyrite

An isometric mineral, 4[AgBr] ; yellow, in surface oxidation deposits of
silver ores in arid climates. Formerly called bromyrite.
CF:iodargyrite




bromellite

A beryllium oxide with dihexagonal-pyramidal crystals from Langban,
Sweden. See:beryllium oxide




bromine

A member of the halogen group of elements and the only liquid nonmetallic
element. A heavy, reddish-brown liquid that volatilizes readily at room
temperature to a poisonous, red vapor with a strong disagreeable odor.
Symbol, Br. Obtained from natural brines from wells; little bromine is
extracted today from seawater. Used in antiknock gasoline, fumigants,
flameproofing agents, water purification compounds, dyes, medicinals, and
sanitizers. Handbook of Chemistry and Physics, 3




bromite

An alternate spelling of bromyrite. See also:bromargyrite




bromlite

A former name for alstonite.




bromocyanide process

Recovering values from refractory or special gold ores, in which cyanogen
bromide (CNBr), or a chemical mixture forming it, is used for treating the
ore. Bennett




bromoform

A colorless, heavy liquid; CHBr3 ; odor and taste similar to those
of chloroform; sp gr, 2.8887. Used in mineralogic analysis and in
assaying. CF:methylene iodide; Clerici solution; Sonstadt solution.
Syn:methenyl tribromide; tribromomethane. CCD, 2




bromyrite

A former name for bromargyrite.




brongniardite

A lead-silver sulfantimonide with 26.2% silver, some of which is
apparently diaphorite and some canfieldite. Also spelled brongniartite.




bronze

An alloy composed mainly of copper and tin. Various other elements may be
added in small amounts for certain specific purposes. A number of copper
alloys are referred to as bronzes, although they contain no tin. The
American Society for Testing and Materials has classified all copper-based
alloys on a basis of composition ranges of the principal alloying
elements. Henderson




bronze mica

See:phlogopite




bronzite

a. A mineral consisting of a ferriferous variety of enstatite, often
having a luster like that of bronze; (Mg,Fe+2 )2 Si (sub
2) O6 ; orthorhombic. Webster 3rd; Dana, 4
b. It is often used as a prefix to the names of rocks containing the
mineral. Rocks of the gabbro family are the most common ones having the
prefix. Fay
c. A name for an orthopyroxene between enstatite and hypersthene in
composition; brown or green; commonly has a bronzelike or pearly metallic
luster.




bronzitite

A pyroxenite composed almost entirely of bronzite. AGI




brood

a. Impurities as extracted with ore. Nelson
b. Corn. The heavier kinds of waste in tin and copper ores. A mixture of
tin and copper ore.




Brookfield viscometer

An electrically operated, rotating-cylinder viscometer in which the drag
is recorded directly on a dial; it has been used in the testing of
vitreous-enamel slips. Dodd




brookite

An orthorhombic mineral, 8[TiO2 ] ; trimorphous with anatase and
rutile; a common accessory mineral in igneous and metamorphic rocks, and
placers. See:titanium dioxide




brooming

The crushing and spreading of the head of a timber pile not fitted with a
driving band when driven into hard ground. Hammond




brouse

Derb. A sort of coarse stopping, made of small boughs of trees, and placed
in back of shaft timbers to prevent rock from falling.




brow

a. Lanc. An underground roadway leading to a working place, driven either
to the rise or to the dip.
b. A low place in the roof of a mine, giving insufficient headroom.
c. A fault plane. Arkell
d. Top of a mine shaft. Also called pit brow. Pryor, 3
e. The projecting upper part or margin of a steep slope just below the
crest; the edge of the top of a hill or mountain, or the place at which a
gentle slope becomes abrupt. See also:apex




brow bar

Mid. A massive curb or beam of timber fixed in the wall of the shaft
across the top of an inset or station. Also called browpiece.




brow bin

An ore bin made by cutting away the floor of the station close to the
shaft. Higham


Brown agitator

See:Pachuca tank




brown clay

a. York. Hessle boulder clay. Arkell
b. See:red clay




brown coal

a. A low-rank coal which is brown or brownish-black, but rarely black. It
commonly retains the structures of the original wood. It is high in
moisture, low in heat value, and checks badly upon drying. AGI
b. A light-brown to seal-brown substance intermediate between peat and
bituminous coal; usually regarded as a variety of lignite, other varieties
being darker or black. It may be distinguished from peat by three rough
criteria: (1) many tissues and fibers can be recognized in peat, but only
a few fibers or none in brown coal; (2) water can be squeezed out of fresh
peat by manual pressure, but not from brown coal; and (3) peat can be cut,
but brown coal cannot. Actually, there is no sharp distinction between
peat and coal. Some have attempted to assign it a higher rank by defining
lignite as containing at least 20% water, brown coal between 10% and 20%
water, and bituminous coal less than 10% water. Hess
c. A type of low-rank coal intermediate between bituminous coal and peat,
and comparatively high in water content. In English-speaking countries,
the terms "brown coal" and "lignite" are synonymous; in Germany and other
parts of Europe, brown coal is restricted to megascopically compact
structural varieties, and lignite is restricted to individual pieces of
wood enclosed in brown coal. It may be subdivided into low-grade brown
coal, consisting of visible vegetable remains, and high-grade brown coal,
a compact, homogeneous, and tough rock. Syn:braunkohle
Tomkeieff
d. Coal of the lowest rank, soft and friable, and having a high inherent
moisture content. BS, 4
e. Unconsolidated lignitic coal having less than 8,300 Btu (8.76 MJ),
(moist, mineral-matter-free).




brown-coal gel

See:dopplerite




brown gummite

See:clarkeite




brown hematite

A misnomer; the mineral bearing this name is limonite, a hydrous mixture
of minerals, whereas true hematite is an anhydrous oxide mineral.
Syn:limonite; brown iron ore. CF:red hematite




Brown horseshoe furnace

An annular turret-type furnace for calcining sulfide ores. Fay




brown iron ore

a. Its approximate formula is 2Fe2 O3 .3H2 O ,
equivalent to about 59.8% iron. Probably a mixture of hydrous oxides.
See also:bog ore
b. See:limonite; brown hematite.




brown ironstone clay

See:limonite




brown matter

Brown matter is found in varying amounts in the attrital matter of all
splint and semisplint coals; it is occasionally present in the attritus of
bright coals. It consists of cell-wall degradation matter and the contents
of cells, which in thin sections are brown and semitranslucent. The term
has no exact equivalent in the Stopes-Heerlen nomenclature. Constituents
with a reflectance between that of vitrinite and fusinite may correspond
in part to brown matter. Some brown matter is identical with semifusinite
and massive micrinite. IHCP




brown mica

See:phlogopite




brown millerite

See:celite




brownmillerite

A mineral, Ca2 (Al,Fe)2 O5 ; a constituent of
Portland cement. Syn:celite




Brown muffle furnace

A mechanically raked, roasting, straight-line-type furnace with a series
of longitudinal combustion flues placed under the hearth. Fay




brown ocher

See:limonite




Brown-O'Hara furnace

A long, horizontal, double-hearth furnace for the treatment of lead ores.
Fay




Brown panel system

a. See:pillar-and-breast
b. Coal mining by long rooms opened on the upper side of the gangway. The
breasts are usually 5 to 12 yd (4.6 to 11.0 m) wide and are separated by
pillars (solid walls of coal broken by crossheadings for ventilation) 5 to
12 yd thick. The pillars are robbed by mining from them until the roof
comes down and prevents further working.
Syn:block system of stoping and filling




brown rock

Tenn. Dark brown to black phosphorite resulting from the weathering of
phosphatic limestone. See also:phosphorite




brown spar

Any light-colored crystalline carbonate mineral that is colored brown by
the presence of iron; e.g., ankerite, dolomite, magnesite, or siderite.
AGI




brownstone

A brown or reddish-brown sandstone with grains generally coated with iron
oxide; specif. a dark, reddish-brown, ferruginous quartz sandstone of
Triassic age.




Brown tank

A cylindrical tank or vat, tall in proportion to its diameter, with the
bottom ending in a 60 degrees cone. Within the tank is a hollow column
extending from the bottom to within about 8 in (20.32 cm) from the top.
The apparatus works on the airlift principle, the aerated pulp in the tube
flowing upward and discharging at the top, while more pulp flows in at the
bottom to take its place. Syn:Brown agitator; Pachuca tank.
Liddell


brown tongs

A long-handled, plierlike device similar to a certain type of blacksmith
tongs used to handle wash or drill rods in place of a safety clamp in
shallow borehole drilling. Also called adjustable pipe tongs; extension
tongs; lowering tongs. Long




brown umber

A brown earthy variety of limonite. See also:limonite




browpiece

A heavy, upright timber used for underpinning in opening a station for a
level in a mine. See also:brow bar




browse

Ore imperfectly smelted, mixed with cinder and clay. Fay




brow-up

Lanc. An inclined roadway driven to the rise. Also called brow; up-brow.




brucite

a. A trigonal mineral, Mg(OH)2 ; brucite group; perfect basal
cleavage; an alteration product of periclase in contact-metamorphosed
limestone; a magnesia refractory raw material.
b. The mineral group amakinite, brucite, pyrochroite, and theophrastite.




Bruckner cylinder

Pac. A form of revolving roasting furnace. See also:Bruckner furnace
Fay




Bruckner furnace

Horizontal cylindrical furnace revolving on end trunnions.
See also:Bruckner cylinder




brulee

A Canadian term used to describe a windfall of dead trees and brush.
Syn:slash




Brunauer, Emmett, and Teller method

A procedure for the determination of the total surface area of a powder or
of a porous solid by measurement of the volume of gas (usually N2 )
adsorbed on the surface of a known weight of the sample. The mathematical
basis of the method was developed by S. Brunauer, P. H. Emmett, and E.
Teller--hence the usual name, B.E.T. method. Dodd




Brunton compass

A compact pocket instrument that consists of an ordinary compass, folding
open sights, a mirror, and a rectangular spirit-level clinometer, which
can be used in the hand or on a staff or light rod for reading horizontal
and vertical angles, for leveling, and for reading the magnetic bearing of
a line. It is used in sketching mine workings, and in preliminary
topographic and geologic surveys on the surface, e.g., in determining
elevations, stratigraphic thickness, and strike and dip.
Syn:pocket transit




Brunton sampler

A mechanical sampling device that automatically selects 1/625 part of the
ore passing through the sampler, by means of an oscillating deflector
placed in a falling stream of the ore. Fay; Pryor, 3




brush

a. To remove rock from the roof or floor of an opening to increase the
height of working (coal mines). See also:brushing
b. In a coal mine, a road through the goaf, gob, or worked-out areas
packed with waste. CTD
c. To clean up fine coal from the floor. CTD
d. Forest of Dean. A rich brown hematite.
e. Mixed load of large and small coal into a colliery tub.
Pryor, 3
f. Mid. To mix gas with air in a mine by buffeting it with a jacket.
g. To rip; to enlarge.
h. To remove bisque in a definite pattern by means of a brush.
See also:bolt-hole brush




brush cleaner

A device consisting of bristles set in a suitable backing used for
cleaning a conveyor belt. It is usually of the rotary type.




brush discharge

In high-intensity electrical fields, discharge from sharp points along a
conductor. Electricity concentrates at these points and charges ambient
molecules of air, which are then repelled, carrying away charge. The
phenomenon is exploited in mineral processing in high-tension separation.
Pryor, 3




brush hook

A short, stout, heavy hooked blade with a sharpened iron edge, attached to
an axe handle; typically used by surveyors for cutting brush. AGI




brushing

a. Scot. That part of the roof or floor of a seam removed to form
roadways.
b. Digging up the bottom or taking down the top of an entry or room, where
the seam of coal is too thin or shallow for the purpose of admitting cars.
See also:brush
c. Cutting or blasting down the roof of a coal seam. Arkell
d. Ripping; normally enlarging a road by taking down the roof, but
extended to sides and floor as well. Also called canch. Mason
e. Removal of dry enamel by brushing through a stencil or along an edge to
produce a design or edging. Bryant




brushing bed

Scot. The stratum brushed or rippled. See also:brush




brushing shot

a. A charge fired in the air of a mine to blow out obnoxious gases or to
start an air current.
b. A shot so placed as to remove a portion of the roof to increase the
height of a haulageway. See also:brush




brushite

A monoclinic mineral, CaHPO4 .2H2 O ; generally massive or
in slender crystals. Syn:metabrushite




brush rake

A rake blade having a high top and light construction. Nichols, 1


brush treatment

A method of treating mine timber in which the timber is painted with a
preservative or is merely dipped into a tank of preservative.
Preservatives used are creosote, zinc chloride, sodium fluoride, and other
chemicals. See also:timber preservation




bruskin

Mid. Lump of coal weighing about 1 lb.




bryle

See:broil




bubble chamber

A device that marks the paths of charged particles by photographing the
train of bubbles they produce as they move through certain superheated
liquids. See also:cloud chamber; spark chamber. Lyman




bubble pickup

Method of testing small grains of minerals to ascertain their response to
flotation collector agents. A bubble of air is pressed down on particles
under water, and then raised and examined to find whether it has lifted
any grains. This is often done by using a single bubble device for
determining fundamental aspects of the mineral-bubble interaction.




bubble pipe

Tube inserted in pulp at regulated depth, through which compressed air is
gently bubbled. The air pressure indicates the pulp density and provides a
means of control. Pryor, 4




bubble pulse

A pulsation attributable to the bubble produced by a seismic charge fired
in deep water. The bubble pulsates several times with a period
proportional to the cube root of the charge, each oscillation producing an
identical unwanted seismic effect. AGI




bubbles

Air introduced near the bottom of a flotation cell containing pulped ore
forms coursing bubbles, which rise through the liquid and emerge as
mineralized bubbles forming a semistable froth column. This depends for
its continuity partly on the surface-active reagents borne by the mineral
in the air-water interphase of each bubble and partly on the aid of
frothing reagents. Pryor, 1




bucaramangite

A resin resembling amber but insoluble in alcohol and yielding no succinic
acid. Fay




Buchner funnel

A porcelain filter shaped to support filter paper on a flat perforated
disk. Pryor, 3




buck

a. A large quartz reef in which there is little or no gold.
See also:bull quartz
b. To push coal down a chute toward a mine car. Zern
c. To break up or pulverize, as to buck ore samples. Webster 3rd
d. To bring or carry, as to buck water. Webster 3rd




bucker helper

One who breaks ore.




bucket

a. See:bailer; calyx.
b. Tubular container equipped with auger or other-type cutting edges used
to make borings in earthy or soft formation by rotary methods.
Long
c. An open-top can, equipped with a bail, used to hoist broken rock or
water and to lower supplies and equipment to workers in a mine shaft or
other underground opening. Long
d. One of the conveying units on a bucket conveyor that lifts the material
from a boot or bin when passing over the lower sprocket and is dumped on
passing over the upper sprocket. The bucket is often made of perforated
metal so that water entrapped will pass through the perforations and back
to the boot. Zern
e. A part of an excavator that digs, lifts, and carries dirt.
Nichols, 1
f. The dipper or scoop at the end of the arm of a bucket dredge.
Webster 3rd




bucket auger

A short helical auger incorporating a steel tube to help hold the cuttings
on the auger during withdrawal from the drill hole. See also:auger
Long




bucket conveyor

A conveyor consisting of a continuous line of buckets attached by pivots
to two endless roller chains running on tracks and driven by sprockets.
The buckets are so pivoted that they remain in an upright position at all
times except when tilted into a dumping position by a cam or other device
placed at any required position on the track. See also:bucket elevator;
gravity-discharge conveyor elevator; pivoted-bucket conveyor.
BS, 5




bucket dredge

A dredge having two pontoons, between which passes a chain of digging
buckets. These buckets excavate material at the bottom of the pond
(paddock) in which the dredge floats, and deposit it in concentrating
devices on the decks. Pryor, 3




bucket drill

Originally developed as an aid in making excavations for cesspools and
septic tanks; now used mostly in drilling holes for concrete piers on
construction jobs. Also called bucket drilling.




bucket elevator

a. An appliance for elevating material, consisting of steel buckets
fastened to an endless belt or chain. It is usually set at steep angles,
around 70 degrees . The load is picked up by discharge from a chute or by
a dredging action in a boot. Its best application is in a plant where
space is restricted and the size of the material is less than 2 in (5.1
cm). Syn:chain elevator
b. See also:centrifugal discharge bucket elevator;
continuous-bucket elevator; double-leg bucket elevator; elevator;
gravity-discharge conveyor elevator; internal-discharge bucket elevator;
positive-discharge bucket elevator; pivoted-bucket conveyor;
grit collector.




bucket elevator belt

A belt fabricated for bucket elevator use, to which an elevator bucket is
attached.




bucket factor

See:fill factor




bucket gate

See:bin gate


bucket-ladder dredge

a. A dredge with a digging mechanism consisting of a ladderlike truss on
the periphery of which is attached an endless chain that rides on sprocket
wheels and on which buckets are attached.
b. A mechanical dredge that uses a chain of heavy buckets rotating over
the dredging arm or ladder to excavate and lift material to the dredging
platform. Syn:bucket-line dredge; ladder-bucket dredge.
See also:dredger




bucket-ladder excavator

A mechanical excavator working on the same principle as a bucket-ladder
dredge, but adapted for use on land. See also:trench excavator
CTD




bucket lift

The discharge pipe of a lifting pump in a mine. Standard, 2




bucket line

An endless line of digging buckets on a dredger or on a bucket elevator.
Pryor, 3




bucket-line dredge

See:bucket-ladder dredge




bucket loader

a. A form of portable, self-feeding, inclined bucket elevator for loading
bulk materials into cars, trucks, or other conveyors.
See also:bucket elevator; portable conveyor.
b. A machine having a digging and gathering rotor and a set of
chain-mounted buckets to elevate the material to a dumping point.
Nichols, 1




bucket pump

a. An iron or wooden receptacle for hoisting ore, or for raising rock in
shaft sinking. Fay
b. A reciprocating lift pump formerly much used in shafts and sinkings.
Nelson




bucket rig

See:rotary bucket drill




bucket sheave

A pulley attached to a shovel bucket, through which the hoist or drag
cable is reeved. Nichols, 2




bucket temperature

The surface temperature of the sea as measured by a bucket thermometer or
by immersing a surface thermometer in a freshly drawn bucket of water.
Hunt




bucket thermometer

A water-temperature thermometer provided with an insulated container
around the bulb. It is lowered into the sea on a line until it has had
time to reach the temperature of the surface water, then withdrawn and
read. The insulated water surrounding the bulb preserves the temperature
reading and is available as a salinity sample. Hunt




bucket tripper

A device that tilts or turns the buckets of a pivoted bucket conveyor,
causing them to discharge. It may be fixed or movable.




bucket-wheel dredge

An hydraulic cutter dredge that uses a bucket wheel excavator in place of
the traditional rotary cutter. The bucket wheel is characterized by its
high cutting torque in both directions and by a positive feed of the
excavated material into the mouth of the dredge pipe. Cruickshank




bucket-wheel excavator

A continuous digging machine originally designed and used in large-scale
stripping and mining of brown coal deposits in eastern Germany. Its
digging mechanism is essentially a boom on which is mounted a rotating
vertical wheel having buckets on its periphery. As the rotating wheel is
pressed into the material to be dug, the buckets cut, gather, and
discharge the material onto a conveyor belt where it is moved to the mined
materials transport system.




bucking hammer

A rectangular piece of cast iron 5 to 6 in (12.7 to 15.24 cm) across,
usually rounded fore and aft with an eye on the back and with a wooden
handle; used for grinding ore on a cast-iron bucking board. Hess




bucking iron

An iron plate on which ore is ground by hand by means of a bucking hammer.
Used extensively for the final reduction of ore samples for assaying.
See also:muller




bucklandite

a. A black variety of epidote containing iron and having nearly
symmetrical crystals.
b. A former name for allanite.




buckle

a. A bend in a piece of drill-stem equipment induced by excessive feed
pressure. Long
b. Deformation of component members of a drill derrick, tripod, or mast,
caused by attempting to hoist too heavy a load or by applying excessive
strain when pulling on stuck casing, etc. Long




buckling length

The length of drill rod that will withstand flexure or bending when
subjected to a specific feed pressure or compressional load. Long




buckling load

The maximum load that can be imposed on a string of drill rods, casing, or
pipe, or on a drill tripod, derrick, or mast without the string buckling;
also, a part being bent or buckled. Long




buck quartz

See:bull quartz


buck reef

A barren vein. Hess




buckshot cinder

Cinder from an iron blast furnace, containing grains of iron. Fay




buck up

a. To screw two threaded members, such as drill rods, together tightly.
Long
b. To shore up with lagging; to brace. Long




buckwheat

Coal size designation, used for anthracite only. Buckwheat is divided into
four sizes: No. 1, or buckwheat; No. 2, or rice; No. 3, or barley; No. 4,
or barley No. 2 or silt (sometimes also called culm or slush). Buckwheat
No. 1 passes through a 1/2-in (12.7-mm) woven wire screen and over a
5/16-in (7.9-mm) woven wire screen, and through a 9/16-in (14.3-mm) round
punched plate and over a 3/8-in (9.5-mm) round punched plate. The American
Institute of Mechanical Engineers has recommended that buckwheat No. 1
shall pass through 9/16-in holes and over 5/16-in holes, a screen with
circular holes being used. See also:anthracite coal sizes




buddle

a. Circular arrangement in which finely divided ore, in water, is
delivered from a central point and flows gently to the perimeter. The
heaviest and coarsest particles settle, while the lightest overflow.
Several variants include concave buddle, with peripheral feed and central
discharge; and continuous buddles, as differentiated from those that are
periodically stopped and cleaned up. Pryor, 3
b. To separate ore from slime or stamp work by means of a buddle.
Standard, 2




Buddy

A shortwall coal cutter designed for light duty on longwall power-loaded
faces and for subsidiary developments. Mason




buddy system

In scuba diving, divers with few exceptions should work in pairs. This is
probably the greatest single aid toward scuba safety, esp. under
unfavorable conditions. The divers should remain in sight of each other.
In poor visibility, they should use a buddy line 6 to 10 ft (1.8 to 3.0 m)
long. Hunt




buffer

a. A pile of blasted rock left against or near a face to improve
fragmentation and reduce scattering from the next blast.
Nichols, 1
b. A substance whose purpose is to maintain a constant hydrogen-ion
concentration in water solutions, even when acid or alkalies are added.
ASM, 1




buffer shooting

See:blanket shooting




bug

a. A bullet or go-devil. See also:bullet
b. Syn. for vug and bug hole (slang). Long




bug dust

a. The fine coal or other material resulting from a boring or cutting of a
drill, a mining machine, or even a pick.
b. Fine, dry, dustlike particles of rock ejected from a borehole by a
current of pressurized air when compressed air, instead of a liquid, is
used as a cuttings removal agent. Syn:cuttings
Long
c. Fine coal or rock material resulting from dry boring, drilling, or the
use of other cutting machines in underground work places. Long




bug dusting

Removing bug dust from an undercut. BCI




buggied

Pennsylvania. Said of coal moved underground in a small car. Hess




buggy

a. A four-wheeled steel car used for hauling coal to and from chutes.
b. A mine car of small dimensions, sometimes used in thin beds.
Hudson
c. Slang for a shuttle car. BCI
d. See:bug dust




bug hole

See:vug




bug light

Slang for a miner's electric cap lamp. BCI




buhrmill

a. A stone disk mill, with an upper horizontal disk rotating above a fixed
lower one. Grist is fed centrally and discharged peripherally. Stones are
dressed periodically, channels being cut to facilitate passage. Also
applied to other rubbing mills; e.g., conical porcelain or steel ones in
which a grooved cone rotates in a close fit in a fixed casing. Also
spelled: burrmill. Pryor, 3
b. A stone mill, consisting of one stationary stone and one revolving
stone, for grinding pigment pastes. Bennett




buhrstone

a. A siliceous rock suitable for use as millstones; e.g., an
open-textured, porous but tough, fine-grained sandstone, or a silicified
fossiliferous limestone. In some sandstones, the cement is calcareous.
Syn:millstone
b. A millstone cut from buhrstone. Also spelled burrstone; burstone.
Syn:burr




buhrstone mill

A grinding mill with two horizontal circular stones, one revolving upon
the other, such as in an old-fashioned grain mill. Mersereau, 2




building stone

A general, nongeneric term for any rock suitable for use in construction.
Whether igneous, metamorphic, or sedimentary, a building stone is chosen
for its properties of durability, attractiveness, and economy.
See also:dimension stone




bulk

Brist. Run-of-mine coal in large quantities.


bulk density

a. The weight of an object or material divided by its volume, including
the volume of its pore spaces; specif. the weight per unit volume of a
soil mass that has been oven-dried to a constant weight at 105 degrees C.
CF:apparent density
b. The ratio of the weight of a collection of discrete particles to the
volume that it occupies. BS, 5
c. The weight of a material, on being compacted in a defined way, per unit
volume (including voids). Taylor
d. The weight per unit volume of any material, including water; the weight
in pounds per cubic foot (kg/m3 ). See also:apparent density;
density; loading weight. Nelson




bulk explosives

Explosives not individually packaged in a form usable in the field.
Includes ammonium nitrate-fuel oil, slurries, water gels, and other
similar blasting agents; often loaded directly into blast holes from a
bulk delivery truck. Federal Mine Safety




bulkhead

a. A watertight dam containing some form of door or removable plate.
See also:dam
b. A tight partition of wood, rock, and mud or concrete in mines for
protection against gas, fire, and water.
c. A masonry diaphragm built across a subaqueous tunnel, where compressed
air is used as a precaution, and to prevent the flooding of an entire
tunnel in case of an accident. It is usually kept some distance in the
rear of the working face and is provided with two air locks; one of them
is an emergency lock near the roof. Stauffer
d. A stone, steel, wood, or concrete wall-like structure primarily
designed to resist earth or water pressure, such as a retaining wall
holding back the ground from sliding into a channel, or a partition
preventing water from entering a working area in a mine. AGI
e. A timber chock in metal mines. Nelson
f. The end of a flume, whence water is carried in iron pipes to hydraulic
workings.
g. A solid crib used to support a very heavy roof. See also:cog; chock.
h. A panel of brick of lesser cross-sectional thickness built into a wall
for ease of replacement or for entrance to the walled chamber.
AISI




bulking

a. The increase in volume of a material due to manipulation. Rock bulks
upon being excavated; damp sand bulks if loosely deposited, such as by
dumping, because the apparent cohesion prevents movement of the soil
particles to form a reduced volume. ASCE
b. The difference in volume of a given mass of sand or other fine material
in moist and dry conditions; it is expressed as a percentage of the volume
in a dry condition. Taylor




bulking agent

Chemically inert materials for increasing the volume of a composition;
e.g., clay. Also called a filler. Bennett




bulk mining

A method of mining in which large quantities of low-grade ore are mined
without attempt to segregate the high-grade portions.
CF:selective mining




bulk mix

A mass of explosive material prepared for use in bulk form without
packaging. Atlas




bulk modulus

The number that expresses a material's resistance to elastic changes in
volume; e.g., the number of pounds per square inch necessary to cause a
specified change in volume. See also:modulus of elasticity;
modulus of rigidity. Leet, 1




bulk modulus of elasticity

The ratio of a tensile or compressive stress, triaxial and equal in all
directions (e.g., hydrostatic pressure), to the relative change it
produces in volume. Roark




bulk oil flotation

a. A flotation process in which large amounts of oil are used.
b. In this process the separation of mineral from gangue is accomplished
by virtue of the fact that minerals of metallic luster, such as sulfides,
or hydrocarbons, such as coal and graphite, are wetted preferentially by
oil in the presence of water and consequently pass into the interface
between oil and water, while gangue or rock is wetted by water and remains
in the medium. See also:flotation




bulk oil separation

A concentration process based on selective wetting of minerals by oil in
the presence of water and in the absence of air. Kirk




bulk pit excavation

Primarily excavation of considerable length as well as of substantial
volume or bulk that must be hauled from the site of operations. Also
called enbankment digging. Carson, 1




bulk sample

One of the large samples of a few hundredweight or more taken at regular,
though widely spaced, intervals. In the case of coal, a car load may be
taken at intervals for size analysis and dirt content. Nelson




bulk sampling

The taking of large samples, which may consist of large-diameter drill
core, the contents of a trench or mine working, or a car or train load of
ore material, for metallurgical testing in mine evaluation. Peters




bulk specific gravity

Ratio of the weight in air of a given volume of permeable material
(including both permeable and impermeable voids normal to the material) at
a stated temperature to the weight in air of an equal volume of distilled
water at a stated temperature. Also called specific mass gravity.
ASCE




bulk strength

The strength per unit volume of an explosive calculated from its weight
strength and density. See also:cartridge strength;
absolute bulk strength.




bulk volume

A term used relative to the density and volume of a porous solid, such as
a refractory brick. It is defined as the volume of the solid material plus
the volume of the sealed and open pores present. Dodd




bulk wide-area excavation

In this kind of excavation, there is complete access to the site from many
directions, and the excavation banks can be sloped flatly on two or more
sides. Usually shallower in depth than bulk pit excavations but larger in
area. CF:bulk pit excavation




bull

a. An iron rod used in ramming clay to line a shothole.
See also:clay iron
b. Aust. See:drag; backstay.
c. N.S.W. To enlarge the bottom of a drilled hole to increase the
explosive charge. New South Wales




Bullard Dunn Process

Electrolytic method of descaling iron and steel and coating the surface
with a protective layer of tin. Pryor, 3




bull clam

A bulldozer fitted with a curved bowl hinged to the top of the front of
the blade. Nichols, 1


bulldog

a. A type of drill-rod-foot safety clamp built somewhat like a spider and
slips, but differing by having the slips or movable jaws attached to, and
actuated by, a foot-operated lever. Long
b. A general term applied to rod and/or casing safety clamps having both
fixed and movable serrated jaws that contact and securely grip the rods or
casing. Long
c. A fishing tool consisting of a steel body, tapered at the top, on which
slide two or more wedge-shaped, serrated-face segments. Lowered into a
tubular piece of lost equipment, such as casing, the serrated segments are
pushed upward toward the narrow part of the body; when the tool is raised,
the segments are forced outward, securely gripping the lost equipment.
Also called bulldog spear; casing dog; casing spear. Long
d. To pull or move a drill machine or auxiliary equipment by means of a
block and tackle or by power derived from a rope used on the drill cathead
or hoist drum. Also called cat; snake. Long




bulldoze

a. To level or excavate an earth surface by means of a heavy, adjustable
steel blade attached to the front end of a tractor or a wheeled vehicle.
Long
b. To reduce broken rock by the use of explosives to a size handy for
raising to the surface. See also:adobe charge; mudcap;
secondary blasting.




bulldozer

a. In nonmetal mining, a laborer who breaks up large stones with a sledge
hammer or pneumatic drill so they will pass through grizzly (grating) in a
limestone mine. DOT
b. A horizontal machine, usually mechanical, having two bull gears with
eccentric pins, two connecting links to a ram, and dies to perform
bending, forming, and punching of narrow plate and bars. ASM, 1
c. A cleaning blade that follows the wheel or ladder of a ditching
machine. Nichols, 1
d. A tractor on the front end of which is mounted a vertically curved
steel blade held at a fixed distance by arms secured on a pivot or shaft
near the horizontal center of the tractor. The blade can be lowered or
tilted vertically by cables or hydraulic rams. It is a highly versatile
piece of earth excavating and moving equipment esp. useful in land
clearing and leveling work, in stripping topsoil, in road and ramp
building, and in floor or bench cleanup and gathering operations. Also
called dozer.




bulled hole

A quarry blasting hole, the bottom of which has been enlarged or chambered
to receive a heavy explosive charge. See also:chambering
Nelson




bullet

a. A small, lustrous, nearly spherical industrial diamond. Long
b. A conical-nosed, cylindrical weight, attached to a wire rope or line,
either notched or seated to engage and attach itself to the upper end of
the inner tube of a wire-line core barrel or other retrievable or
retractable device placed in a borehole. Syn:bug; go-devil; overshot.
Long
c. A bullet-shaped weight or small explosive charge dropped to explode a
charge of nitroglycerin placed in a borehole. Long




bull gear

a. A toothed driving wheel that is the largest or strongest in the
mechanism. Nichols, 1
b. A gear or sprocket that is much larger than the others in the same
power train. Nichols, 1




Bullgrader

Trade name for an International (formerly Bucyrus-Erie) angling bulldozer.
Nichols, 1




bullies

Fragments of country rock enclosed in a mineral vein. Arkell




bulling

The firing of explosive charges in the cracks of loosened rock. The clay
stemming is forced around the charge by a bulling bar.
See also:bulled hole




bulling shovel

A triangular, sharp-pointed shovel used in ore dressing. Also called
vanning shovel. Fay




bullion

a. A concretion found in some types of coal; composed of carbonate or
silica stained by brown humic derivatives; often a well-preserved plant
structure forms the nucleus. Also called coal ball. AGI
b. Lanc. Nodule of clay ironstone, pyrite, shale, etc., that generally
enclose a fossil.
c. Refined gold or silver, uncoined, in the shape of bars, ingots, or
comparable masses. ASM, 1




bullion bar

Refined gold or silver in the form of bars of convenient sizes and weights
for handling and storage. Henderson




bullion content

Bullion (gold or silver) weight in a parcel of mineral or metal changing
hands. The major value is that of the carrier (e.g., argentiferous lead),
but payment is made both for this and for the precious metal.
Pryor, 3




bull ladle

Usually the largest ladle in a foundry.




bull mica

Large clusters of diversely oriented and partially intergrown crystals of
muscovite with a little interstitial albite and quartz. Skow




bullnose bit

A noncoring bit having a convex, half-hemispherical-shaped crown or face.
Also called wedge bit; wedge reaming bit; wedging bit.
See also:plug bit




bull pup

A worthless mining claim.




bull quartz

White massive quartz, essentially free of accessory minerals and valueless
as ore. Syn:bastard quartz; buck quartz. AGI




bull's-eye

A nodule of pyrite in roofing slate.




bull's-eye tuyere

A tuyere discharging in the center of a hemispherical plate.
Standard, 2




bull shaker

A shaking chute where large coal from the dump is cleaned by hand.
Zern


bull wheel

a. The large winding drum on which the drill cable or bull rope of a churn
or cable-tool drill is wound. Long
b. Large sheave at the top of the mineshaft headframe over which the cage-
or skip-hoist rope passes. Long
c. An underground sheave wheel; particularly, the wheel around which the
tail rope is passed beyond each terminal of a tail-rope haulage system.
d. The pulley that rotates the camshaft of a stamp battery. Nelson




bully

A developing heading driven to the dip, usually the full dip of the coal
seam; worked by rope haulage. Nelson




bullying

See:springing




bumboat

A small boat equipped with a hoist and used for handling dredge lines and
anchors. Nichols, 1




bump

a. Any dull, hollow sound produced in a coal seam or associated strata as
a result of mining operations. See also:outburst; crump; rock bump;
rock burst. Nelson
b. Sudden failure of the floor or walls of a mine opening, generally
accompanied by a loud report and a sharp shock or jar. Long
c. An earth tremor occasioned by a rock failure, when that failure causes
no damage to the workings. Spalding
d. A noise caused by a break in the roof underground. Mason
e. The actual movement due to the roof break. Mason
f. A sudden floor uplift due to a break in the floor. Mason
g. In coal mining, shock due to the movement of coal, floor, or roof
strata, with sufficient violence to be heard and to shake the workings.
Pryor, 3
h. Rebound caused by a sudden release of tension on the drill stem when a
core breaks or snaps free of the bottom of the borehole. Long
i. A sharp, upward blow applied to the drivepipe, casing, or drill stem
with a drive hammer. Long




bumper

a. A worker who pushes loaded cars or cans into a station for the hooker
and removes the empties. Hess
b. A device used to loosen the tools when drilling is carried on without
jars. Porter
c. A fender for lessening the jar caused by the collision of cars or other
moving equipment. Jones, 1
d. See:catch
e. A machine used for packing molding sand in a flask by repeated jarring
or jolting. ASM, 1




bumper block

An impeding device at dumping locations where there is a hazard of vehicle
overtravel. Federal Mine Safety




bumper post

Barrier of heavy steel construction anchored at a track ending to stop
rolling railroad cars and prevent their being thrown off center or
derailed. Best, 1




bumping table

See:shaking table




bumping trough

An appliance for handling broken rock in flat mine stopes. A sheet-steel
trough is hung from chains and arrested at one end of its swing by a bump
stop, so that the ore slides forward. Pryor, 3




bumps

Sudden, violent expulsion of coal from one or more pillars, accompanied by
loud reports and earth tremors. Bumps occur in coal mines where a strong,
thick, massive sandstone roof rests directly on the coal with no
cushioning layer of shale between. The breaking of this strong roof as the
seam is mined causes violent bumps and the crushing and bursting of
pillars left for support. There are two distinctive types of bumps: (1)
pressure bumps, which appear to be due to the unit loading of a pillar
being too great for its bearing strength, and where the coal roof and
floor are strong, the pillar is ruptured suddenly and with violence; and
(2) shock bumps, which are thought to be due to the breaking of thick,
massive, rigid strata somewhere above the coalbed, which causes a great
hammerlike blow to be given to the immediate roof, which it transmits as a
shock wave to the coal pillar or pillars. Kentucky; Lewis




bunched seismometers

Group of seismometers located at short intervals at the same seismometer
station and electrically interconnected. Syn:multiple seismometers
Schieferdecker




bunchy

a. An orebody containing small scattered masses of bunches of ore.
Weed, 2
b. A mine that is sometimes rich and at other times poor. Hess




bund

Any artificial embankment used to control the flow of water in a river or
on irrigated land. The term is applied extensively in India to large low
dams and dikes and also to the small ridges between rice fields. Also, an
embanked causeway or thoroughfare along a river or the sea. AGI




bunker

A vessel for the storage of materials; the lowermost portion is usually
constructed in the form of a hopper. Also called bin.
See also:surge bunker; underground bunker. BS, 5




bunker coal

Applied to coal consumed by ocean steamers, tugs, ferryboats, or other
steam watercraft. Also called bunkers. Fay




bunker conveyor

A high-capacity conveyor that takes peaks of production from another
conveyor and retains and/or discharges the material when production drops.
Such a conveyor may be laid under or alongside a trunk belt near its
discharge end. The floor of the bunker comprises a slow-moving steel plate
conveyor operated by hydraulic or other power. A movable plow plate,
situated over the trunk belt, diverts the material sideways into the
bunker conveyor. See also:underground bunker




bunker gate

See:bin gate




bunkering capacity

The capacity of anything. It may be expressed as a tonnage or as so many
hours of normal production. Bunkering capacity may be provided at the
surface and at critical points underground. Nelson




bunney

a. A mass of ore not lying in a regular vein. Also spelled bunny, bonny,
bonney. Nelson
b. Corn. An isolated body of ore. Hess




bunny

See:bunney


bunsenite

A pistachio-green isometric mineral, NiO, of the periclase group.




Bunsen photometer

A visual photometer in which a simple mirror system enables both sides of
the test plate, consisting of a screen of opaque-white paper on which is a
grease spot, to be viewed at the same time. That portion of the screen on
which the grease lies is translucent to light, so that there is a
difference in brightness between the grease spot and the surrounding
ungreased paper. When comparing sources, one on either side of the
photometric bench, the point of balance is such that, as seen in the
mirror, both sides of the screen show equality of contrast between the
grease spot and its white surroundings. Roberts, 2




bunton

a. A steel or timber element in the lining of a rectangular shaft. Buntons
may be 6 in by 5 in or 6 in (15.2 cm by 12.7 cm or 15.2 cm) square and
extend across the shaft at intervals of 4 ft to 8 ft (1.2 m to 2.4 m).
They serve to reinforce the barring and also carry the cage guides. Rolled
steel joists are now generally used as buntons. See also:divider;
wallplate. Nelson
b. A timber placed horizontally across a shaft. It serves to brace the
wallplates of the shaft lining and also, by means of planks nailed to
them, to form separate compartments for hoisting or ladderways.




bunton racking

Timber pieces used in the support of rectangular shafts.
See also:wallplate




buoyant weight

The apparent weight of a string of drill tools suspended in a
liquid-filled borehole. The apparent weight is the weight of the drill
string in air less the weight of the liquid displaced by the drill string
when suspended in a liquid-filled borehole. Long




buratite

An aurichalcite containing calcium monoxide, probably as a mechanical
admixture. Weed, 1




burbankite

A hexagonal mineral, (Na,Ca)3 (Sr,Ba,Ce)3 (CO3 ) (sub
5) .




burden

a. The distance from the borehole and the nearest free face or distance
between boreholes measured perpendicular to the spacing (usually
perpendicular to the free face).
b. All types of rock or earthy materials overlying bedrock.
See also:cover; mantle; overburden. Long
c. Valueless material overlying ore, esp. that removed by stripping.
Frequently called overburden. Webster 2nd
d. The resistance that an explosive charge must overcome in breaking the
rock adjacent to a drill hole in mining. Webster 3rd
e. The tonnage or cubic yards of rock, ore, or coal that an explosive
charge is expected to break. Nelson
f. The distance between the charge and the free face of the material to be
blasted. Fay
g. See:line of least resistance
h. The charge of a blast furnace exclusive of the fuel; also, the ratio of
the ore to the total charge.




burdening the furnace

Determining the proper proportions of ore, coke, and limestone for a blast
furnace charge. Mersereau, 2




burgee

Small coal suitable for furnaces or engines. Arkell




Burgers vector

In crystal structures, dislocations locally alter coordination polyhedra
with the result that regular polyhedra several atomic diameters distant
are offset from their regular positions. The Burgers vector is a measure
of that offset, being normal to edge dislocations and parallel to screw
dislocations.




buried hill

A hill of resistant older rock over which later sediments were deposited.
The overlying sedimentary beds have the form of an anticline as the result
of original dip, unequal compaction, etc. The term was first applied to
the underlying beds of the Healdton Field, OK. AGI




buried outcrop

See:blind apex




buried placer

a. Old placer deposit that has been buried beneath a lava flow or other
strata.
b. See:deep lead




burkeite

An orthorhombic mineral, Na6 (CO3 )(SO4 )2 ;
in small flat crystals, twins, and nodules; at Searles Lake, CA.
Syn:teepleite




burl

An oolith or nodule in fireclay. It may have a high content of alumina or
iron oxide. AGI




Burleigh

A miner's term for any heavy two-person drill. The Burleigh was the first
successful machine rock drill. Hess




burley clay

A clay containing burls; specif. a diaspore-bearing clay in Missouri,
usually averaging 45% to 65% alumina. See also:diaspore clay
AGI




burn

a. To permit a bit to become overheated in use. Long
b. To calcine. Long
c. To pulverize with very heavy explosive charges. Nichols, 1




burn cut

Type of parallel hole or holes cut for tunnel blasting; centrally located
and not containing explosives. Outer loaded holes are designed to break
the cut.




burned

Said of slate or other impurity that adheres tightly to coal. Similarly,
coal is said to be "burned to the roof" when it is hard to separate the
roof rock from the coal. Fay


burned bit

As a result of high-speed, excessive pressure, and poor water circulation,
sufficient heat may be generated at the bottom of a borehole to cause a
diamond crown to soften, resulting in displacement of diamonds and a
ruined bit. Nelson




burned cut

A cut made in the face of a heading for which three or four holes are
drilled normal to the face and in a triangle or square, 12 to 18 in (30.48
to 45.72 cm) on a side, with another hole in the center. One, two, or
three holes are loaded and shot; the others relieve the pressure and
induce breaking. A cavity is formed to which other shots in the face
readily break. Used for esp. tough ground. Also called Michigan cut;
woodchuck cut. Hess




burned lime

Calcium oxide (quicklime) formed from limestone, or other forms of calcium
carbonate, which has been calcined at high temperature to drive off the
carbon dioxide. See also:burnt lime




burn in

a. To run a bit with too little coolant until the heat generated by the
bit fuses the cuttings, core, bit, and the bottom of the borehole.
Long
b. To deliberately run a bit with reduced amount of coolant until the core
is jammed inside the bit. Long




burning house

A furnace in which sulfide ores are calcined to form gaseous SO2
and leave the metal oxide, or in the case of noble metals, the metal
itself.




burning oil

A common name for kerosine.




burning out

A loose term, usually used to describe the wearing away of furnace linings
without a known reason.




burno man

A laborer who gets ore ready for a mechanical shovel or a hand shoveler.
Hess




burnout

A situation encountered in coal seams, usually near the outcrop, where the
coal has undergone combustion and burned. Initiation sources could include
lightning, forest fires, etc.




burn out

To salvage diamonds from a used bit by dissolving the matrix alloy with an
acid or by use of an electrolytic process. Long




Burnside boring machine

This machine has been specially developed for boring in all types of
ground, and incorporates a very important feature, that of controlling the
water immediately if it is tapped. In boring, the hole is first prepared
for the reception of a special rubber ring, two iron plates, and two
wedges. When these are properly adjusted, the rubber washer is compressed
and powerfully gripped on the sides of the borehole to effect a sound and
reliable joint. If during boring operations water should rush out and the
bore rods cannot be withdrawn, the two handwheels are screwed in; this
presses india-rubber plugs onto the bore rods and effects a watertight
joint. Mason




burnt alum

Alum that has been dried at 200 degrees C, and powdered; AINH4 (SO
4 )2 or AIK(SO4 )2 . A caustic.
Syn:dried alum; exsiccated alum.




burnt iron

a. Iron which by long exposure to heat has suffered a change of structure
and become brittle. It can be restored by careful forging at welding heat.
Fay
b. In the Bessemer and open-hearth processes, iron that has been exposed
to oxidation until all of its carbon is gone, and an oxide of iron has
been formed in the mass. Fay




burnt lime

Calcitic lime, CaO, or dolomitic lime, CaO.MgO. See also:burned lime




burnt metal

Metal that has become oxidized by overheating, and so is rendered useless
for engineering purposes. CTD




burnt stone

a. An antique carnelian, such as is sometimes found in ancient ruins and
has apparently been acted on by fire. Fay
b. A gemstone with color changed by heating; e.g., amethyst, which changes
from purple to clear; or tiger-eye, which changes from yellowish-brown to
reddish brown. Syn:heat-treated stone
See also:heated stone




burr

a. A term used in England for a rough or hard stone, such as a compact
siliceous sandstone esp. hard to drill. Also spelled bur. AGI
b. A knob, boss, nodule, or other hard mass of siliceous rock in a softer
rock; a hard lump of ore in a softer vein. AGI
c. See:buhrstone




burr rock

An aggregate of muscovite books and quartz. Skow




burrstone

See:buhrstone




burst

An explosive breaking of coal or rock in a mine due to pressure. In coal
mines bursts may or may not be accompanied by a copious discharge of
methane, carbon dioxide, or coal dust. Also called outburst; bounce; bump.
See also:rock burst




burster

a. A hydraulic mechanism that, when inserted into a large-diameter
shothole, breaks down the strata by means of pistons operating
transversely. BS, 12
b. Scot. A shot in a coal seam that has not been sheared or undercut.
Equivalent to "shot off the solid." Also called bursting shot.


bursting

The phenomenon sometimes exhibited by refractories containing chrome ore,
when exposed to iron oxide at high temperature, of having the exposed face
swell and grow until it breaks away from the brick mass. ARI




bursting charge

A small charge of fine powder placed in contact with a charge of coarse
powder to ensure the ignition of the latter. Fay




bursting time

The time between the application of an electric current and the setting
off of an explosive charge. In seismic prospecting, it may be necessary to
take into account the maximum difference in time lag between the bursting
of the earliest and latest detonators in a series. In a series firing
current of over 1 A direct current, the maximum difference with submarine
seismic detonators is always less than 1 ms. Nelson




Burt filter

A stationary, intermittent filter in which the leaves are suspended
vertically in a cylindrical vessel set on a considerable incline. The
leaves are therefore ellipses. The slime cake is discharged by introducing
air and water into the interior of the leaf. There is also a Burt filter
of the continuous-rotating-drum type. Liddell




burton

Any of several arrangements of hoisting tackle; usually one with a single
and a double block. Webster 3rd




Bushveld Complex

A great intrusive igneous body in the Transvaal, South Africa, that has
undergone remarkable magmatic differentiation. It is by far the largest
layered intrusion known. The Bushveld is the leading source of chromite.
AGI




Buss table

Shaking table for treatment of ore sands, comprising a deck supported by a
Ferraris truss moved by eccentric. Pryor, 3




bustamite

A triclinic mineral, (Mn,Ca)Si3 O9 .




buster shot

See:breaking-in shot




bus wire

Expendable heavy-gage bare copper wire used to connect detonators or
series of detonators in parallel in underground blasting.




but

Scot. Outward; toward the shaft; outbye.




butane

a. A flammable gaseous hydrocarbon, commonly bottled for use as fuel.
b. A gaseous flammable paraffin hydrocarbon, C4 H10 ,
occurring in either of two isometric forms: n-butane, CH3 CH (sub
2) CH2 CH3 ; or isobutane, CH3 CH(CH3 ) (sub
2) . The butanes occur in petroleum and natural gas. AGI




butane flame methanometer

An instrument giving a continuous record of the methane concentration in
mine air. It uses a small flame burning butane in a gauze-protected
enclosure. Instead of observing the cap, thermocouples are used to show
the increased temperature above the flame, and the resulting signal is
displayed on a recording milliammeter. The instrument runs for at least a
week and is accurate to about 0.05% methane.
See also:methane tester type S




Butchart table

A shaking table, toggle-actuated, with its deck supported in slipper
bearings, and carrying curved riffles. Pryor, 3




butlerite

Arg. A monoclinic mineral occurring as oriented intergrowths with
parabutlerite. A hydrous sulfate of iron. Am. Mineral., 1




buetschliite

A trigonal mineral, K2 Ca(CO3 )2 ; dimorphous with
fairchildite. Also spelled buetschliite.




butt

a. Opposite of face, coal exposed at right angles to the face, and in
contrast to the face, generally having a rough surface. Also called end in
Scotland. BCI
b. The butt of a slate quarry is where the overlying rock comes in contact
with an inclined stratum of slate rock.




butt cleat

The minor cleat system, or jointing, in a coal seam, usually at right
angles to the face cleat. Syn:end cleat
AGI




butte

a. A conspicuous hill or small mountain with relatively steep slopes or
precipitous cliffs, often capped with a resistant layer of rock, and
representing an erosion remnant carved from flat-lying rocks. The summit
is smaller in extent than that of a mesa; many buttes in the arid and
semiarid regions of the Western United States result from the wastage of
mesas. Syn:mesa-butte
b. An isolated hill having steep sides and a craggy, rounded, pointed, or
otherwise irregular summit; e.g., a volcanic cone (such as Mount Shasta,
CA, formerly known as Shasta Butte) or a volcanic butte. Etymol: French,
knoll, hillock, inconspicuous rounded hill; rising ground. Pron: bewt.
AGI




butt entry

a. An entry driven at right angles to the butt. BCI
b. The gallery driven at right angles with the butt cleat. An end-on
entry.
c. A gallery driven parallel with the main cleat of the coal seam.
See also:entry




butterball

A clear-yellow, rounded segregation of very pure carnotite found in the
soft sandstone of Temple Rock, San Rafael Swell, UT. AGI


Butters and Mein distributor

A turbo distributor that spreads sand evenly around a circular leaching
tank in gold cyanidation. Pryor, 3




buttgenbackite

A hexagonal mineral, Cu19 Cl4 (NO3 )2 (OH)
32 .2H2 O .




butt heading

See:butt entry




butt joint

a. A joint between two abutting members lying approx. in the same plane. A
welded butt joint may contain a variety of grooves. ASM, 1
b. See:butt cleat




buttock

a. A corner formed by two coal faces more or less at right angles, such as
the end of a working face; the fast side; any short piece of coal approx.
at right angles to the face; a rib; the rib side. See also:rib
Mason
b. Eng. That portion of a working face of coal, next to be taken down.
Fay
c. The rib of coal exposed at one or both ends of a longwall face, to
enable a cutter loader to commence its run; the coal removed by a cutter
loader. See also:stable; web. Nelson
d. Coal that has been undercut and is ready to be broken. Pryor, 3




button

a. A globule of metal remaining in an assaying crucible or cupel after
fusion has been completed. ASM, 1
b. That part of a weld that tears out in the destructive testing of
spot-seam or projection-welded specimens. ASM, 1
c. Globule of lead formed during fire assay of gold or silver ore.
Pryor, 3




button balance

A small, very delicate balance used for weighing assay buttons.




button fusion test

See:button test




button rope conveyor

See:rope and button conveyor




button test

A test designed to determine relative fusibility of frit or powder. So
called because the completed specimens resemble buttons.




butt shot

In coal mining, a charge placed so that the face or burden is nearly
parallel with the borehole.




butt side

The side of the working face of a coalbed in which the joints or cleats
are least pronounced, as distinguished from the face side in which the
joints are most pronounced. Hess




butt weld

A weld made between two abutting unscarfed ends or edges without
overlapping. Both the pin- and box-thread portions of petroleum drill pipe
generally are butt-welded electrically to upset end tubing to form a
complete section of drill pipe or rod. Long




butt-welded tube

A tube made by drawing mild steel strip through a bell, so that the strip
is coiled into a tube, the edges being then pressed together and welded.
CTD




butyl rubber

Synthetic material, copolymer of butadiene and isobutane. Pryor, 3




Buxton test

One of a set of tests carried out in a gallery at the Safety in Mines
Research Station at Buxton, England. The tests are made to determine the
likelihood or limits at which an explosive will ignite gas or coal dust,
before it can be placed on the official permitted list.
See also:permitted explosive




BW

Letter name specifying the dimensions of bits, core barrels, and drill
rods in the B-size and W-group wireline diamond drilling system having a
core diameter of 42 mm and a hole diameter of 60 mm. Syn:BX
Cumming, 2




BX

Letter name specifying the dimensions of core, core barrels, and casing in
the B-size and X-series wireline diamond drilling system having a core
diameter of 42 mm and a hole diameter of 60 mm. The BX designation for
coring bits has been replaced by the BW designation. Syn:BW
Cumming, 2




bye water

See:bank water




bypass

a. A short passage used to get by or around a place it is not advisable to
cross; e.g., a mine shaft. Also spelled byepass.
b. To pass to the side of an obstruction in a borehole by deflecting the
hole. Syn:drill by
c. An alternative path, in a duct or pipe, for a fluid to flow from one
point to another, with the direction determined by the opening or closing
of valves or dampers in the main line as well as in the bypass.
Strock, 2
d. An arrangement of screens and chutes, or of piping, allowing material
to be passed around a given part of a flow line. Much used to avoid
feeding fine ore through a relatively coarse crusher, thus reducing load,
wear, and chance of blockage. Pryor, 3
e. A small passage to permit equalization of the pressure on the two sides
of a large valve so that it may be readily opened or closed.




bypit

Scot. A pit nearer the outcrop than the engine pit; an air pit.


byproduct

A secondary or additional product; e.g., gallium is commercially recovered
from the processing of bauxite to alumina. See also:coproduct




byproduct oven

A coke oven consisting of a series of long, narrow chambers arranged in
rows, and heated by flues in which are burned a portion of the combustible
gases generated by the coking of the coal. All of the volatile products
are saved and collected as ammonia, tar, gas, etc. Fay




byproducts of coal

The products obtained from coal by destructive distillation and other
processes. Cooper




byssolite

An olive-green asbestiform variety of tremolite-actinolite. The term is
used in the gem trade for a variety of quartz-containing, greenish,
fibrous inclusions of actinolite or asbestos.




bystroemite

a. A tetragonal mineral, MgSb2 O6 .
b. A former name for a monoclinic polymorph of pyrrhotite. Also spelled
bystromite.




bytownite

A triclinic mineral, (Ca,Na)[Al,Si)AlSi2 O8 ] having 90 to
70 mol % Ca and 10 to 30 mol % Na; of the plagioclase series of the
feldspar group; prismatic cleavage; white to gray; forms phenocrysts in
some basalts and layered mafic-ultramafic intrusions




by-wash

A channel or spillway designed to carry surplus water from a dam,
reservoir, or aqueduct in order to prevent overflow. AGI