Appendix:Dictionary of Mining, Mineral, and Related Terms/C/2

car

a. A wheeled vehicle used for the conveyance of coal or ore along the gangways or haulage roads of a mine. Also called mine car; tramcar; tub; wagon; mine wagon.

b. A wheeled carrier that receives and supports the load to be conveyed. Generally attached to a chain, belt, cable, linkage, or other propelling medium. See also: tray.

caracolite

A monoclinic mineral, Na (sub 3) Pb (sub 2) (SO (sub 4) ) (sub 3) Cl ; pseudohexagonal; forms crystalline incrustations.

Carapella's reagent

An etchant consisting of 5 g of ferric chloride dissolved in 96 mL of ethyl alcohol to which has been added 2 mL of hydrochloric acid; used in etching nonferrous metals and manganese steels.

carat

a. A unit of weight for diamonds, pearls, and other gems; formerly equal to 3-1/6 troy grains (205 mg). The international metric carat (abbreviated M.C.) of 200 mg was made the standard in the United States in 1913, as it was the standard in Belgium, Denmark, Great Britain, France, Germany, Japan, the Netherlands, and Sweden. A carat grain is 1/4 carat. Syn: international metric carat. Not to be confused with "karat." CF: point.

b. Employed to distinguish the fineness of a gold alloy, and meaning 1/24 part. Pure gold is 24-carat gold. Goldsmiths' standard is 22 carats fine; it contains 22 parts of gold, 1 part of copper, and 1 part of silver.

caratage

See: carat weight.

carat count

The number of near-equal-size diamonds having a total weight of 1 carat or 200 mg; hence, 40 small diamonds weighing 1 carat would be called 40-count diamonds, or 8 diamonds weighing 1 carat would be called 8-count diamonds.

carat-goods

Diamonds averaging about 1 carat each in weight.

carat loss

Amount of diamond material lost or worn away by use in a drill bit, expressed in carats.

carat weight

Total weight of diamonds set in a drill bit, expressed in carats. Also called caratage.

carbankerite

Any coal microlithotype containing 20% to 60% by volume of carbonate minerals (calcite, siderite, dolomite, and ankerite).

carbargilite

Any coal microlithotype containing 20% to 60% by volume of clay minerals, mica, and in lesser proportions, quartz.

carbide

a. A commercial term for calcium carbide formerly used in miner's lamps.

b. The carbide compound of tungsten. c. The bit-crown matrices and shaped pieces formed by the pressure molding and sintering of a mixture of powdered tungsten carbide and other binder metals, such as cobalt, copper, iron, and nickel. See also: cemented carbide; sintered carbide. d. A compound of carbon with one or more metallic elements.

carbide insert

Shaped piece of a hard metal compound, sometimes inset with diamonds, formed by the pressure molding and sintering of a mixture of powdered tungsten carbide and other binder metals, such as iron, copper, cobalt, or nickel. Inset into holes, slots, or grooves in bits, reaming shells, or core barrels, the hard metal pieces become cutting points or wear-resistant surfaces. Also called carbide slug.

carbide lamp

A lamp that is charged with calcium carbide and water and burns the acetylene generated. Syn: acetylene lamp.

carbide miner

A push-button mining machine with a potential range of 1,000 ft (304.8 m) into a seam from the highwall, a maximum production of some 600 st (544 t) per shift, and a recovery of 65% to 75% of the coal within the reach of the machine. This unit is a continuous miner working controlled from outside the seam of coal. The operator can control both the vertical and horizontal direction of the cutting heads as shown on an oscilloscope screen. As the cutting head advances into the coal seam, it drags a series of conveyor sections behind it, which in turn deposit the coal into a truck.

carbides

Compounds of carbon with iron and other elements in steel; e.g., Fe (sub 3) C (cementite), Fe (sub 4) W (sub 2) C , and Cr (sub 4) C (sub 2) .

carbide slug

See: carbide insert.

carbide tool

A cutting tool--made of tungsten carbide, titanium carbide, tantalum carbide, or combinations of them, in a matrix of cobalt or nickel--having sufficient wear resistance and heat resistance to permit high machining speeds.

Carbite

Trade name for an explosive.

carbo-

A combining form meaning carbon, as in carbohydrate.

carbo

A Latin name for charcoal, later transferred to fossil coal.

Carbo

Clay-bonded silicon carbide; used as refractory.

carbocher

A variety of hydrocarbon containing about 8% rare earths and found enclosed in a mineral kondrikite. From the Khibine Peninsula, Russia.

carbodynamite

A form of dynamite in which fine charcoal is used as the absorbent.

carbohumin

An amorphous carbonaceous substance, a product of decomposition of plants and impregnating plant remains, which undergo transformation into coal. It is assumed to be present in coal in the form of structureless jelly. Syn: jelly; fundamental jelly; fundamental substance; gelose; jelly; vegetable jelly.

carbolic

a. Of, pertaining to, or derived from carbon and oil; of or pertaining to coal-tar oil.

b. Of or pertaining to carbolic acid.

carbolic acid

White; crystalline; deliquescent; C (sub 6) H (sub 5) OH; a burning taste; and an odor resembling that of creosote. Contained in the heavy oil of coal tar, from which it is distilled at between 165 degrees C and 190 degrees C. It is a caustic poison. Antidotes are epsom salts, alcohol, and heat. See also: phenol.

carbolite

A byproduct in iron smelting, consisting of calcium-aluminum silicon carbide; used as a substitute for calcium carbide.

carbon

a. A nonmetallic element, found free in nature in three allotropic forms: amorphous, graphite, and diamond. A fourth form, known as "white" carbon, is now thought to exist. Symbol, C. Graphite is one of the softest known materials, while diamond is the hardest. Occurs as a constituent of coal, petroleum, natural gas, and all organic compounds. The isotope, carbon 14, is radioactive and is used as a tracer in biological and organic chemical research.

b. Rand term for thucolite in banket ore. c. A gray-to-black, opaque, tough, hard cryptocrystalline aggregate of diamond crystals occurring in irregular shapes and sizes. It is classed as an industrial diamond and formerly was used extensively as a cutting-medium inset in diamond-drill bits. More recently, only occasionally used in diamond bits and other tools. Also called black diamond; carbonado. See also: diamond.

carbon-14

A radioactive isotope of carbon having the atomic weight of 14, produced by collisions between neutrons and atmospheric nitrogen. It is useful in determining the age of carbonaceous material younger than 30,000 years old. See also: carbon; carbon-14 dating.

carbon-14 dating

A method of determining an age in years by measuring the concentration of carbon-14 remaining in an organic material, usually formerly living matter, but also water, bicarbonate, etc. The method is based on the assumption that assimilation of carbon-14 ceased abruptly on the death of an organism and that it thereafter remained a closed system. The method is useful in determining ages in the range of 500 to 30,000 years or 40,000 years, although it may be extended to 70,000 years by using special techniques involving controlled enrichment of the sample in carbon-14. Syn: radiocarbon dating; carbon dating.

carbonaceous

a. Coaly, containing carbon or coal, esp. shale or other rock containing small particles of carbon distributed throughout the whole mass.

b. Carbonaceous sediments include original organic tissues and subsequently produced derivatives of which the composition is organic chemically.

carbonado

Cryptocrystalline diamond; compact, tough, opaque, dark-gray to black, cleavage absent; generally in rounded masses, also in angular broken fragments. Principal source is Bahia, Brazil, but also found elsewhere in South America and Africa. Syn: black diamond; carbon diamond. CF: ballas.

carbonado bit

See: carbon bit.

carbon adsorption

Recovery of dissolved soluble constituents onto activated carbon due to some form of chemical sorption at the active sites. Carbon adsorption is particularly useful for removing gold and silver from cyanide leach solutions or dissolved organics from process solutions.

carbonate

a. A compound containing the acid radical CO (sub 3) of carbonic acid. Bases react with carbonic acid to form carbonates. CF: carbonate.

b. A mineral compound characterized by a fundamental anionic structure of (CO (sub 3) ) (super 2-) . Calcite and aragonite, CaCO (sub 3) , are examples of carbonates. CF: borate; nitrate. c. A sediment formed by the organic or inorganic precipitation from aqueous solution of carbonates of calcium, magnesium, or iron; e.g., limestone and dolomite. See also: carbonate rock. d. Ores containing a considerable proportion of metal carbonates. e. Salts of carbonic acid, H (sub 2) CO (sub 3) .

carbonate-fluorapatite

See: dehrnite.

carbonate hardness

Hardness of water, expressed as CaCO (sub 3) , that is equivalent to the carbonate and bicarbonate alkalinity. When the total alkalinity, expressed as CaCO (sub 3) , equals or exceeds the total hardness, all the hardness is carbonate. It can be removed by boiling and hence is sometimes called temporary hardness, although this syn. is becoming obsolete. Syn: hardness.

carbonate leach

a. Metallurgical process for dissolution of metal values by means of a sodium carbonate solution. Used on high-lime ores.

b. Dissolution of uranium with an aqueous solution of sodium carbonate in the presence of sufficient oxygen to render uranium hexavalent. c. Tungsten autoclave dissolution.

carbonate mineral

A mineral formed by the combination of the radical (CO (sub 3) ) (super 2-) with cations; e.g., calcite, CaCO (sub 3) .

carbonate of barium

See: witherite.

carbonate of calcium

See: calcite.

carbonate of strontium

See: strontianite.

carbonate rock

A rock, such as limestone, dolomite, or carbonatite, that consists chiefly of carbonate minerals; specif. a sedimentary rock composed of more than 50% by weight of carbonate minerals. Syn: calcareous rock.

carbonate sand

A sand derived predominantly from carbonate material such as corals, mollusc shells, algae, etc.

carbonation

a. A process of chemical weathering involving the transformation of minerals containing calcium, magnesium, potassium, sodium, and iron into carbonates or bicarbonates of these metals by carbon dioxide contained in water (i.e., a weak carbonic-acid solution). Syn: carbonatization.

b. Introduction of carbon dioxide into a fluid.

carbonatite

A carbonate rock of apparent magmatic origin, generally associated with kimberlites and alkalic rocks. Carbonatites have been variously explained as derived from magmatic melt, solid flow, hydrothermal solution, and gaseous transfer.

carbonatization

a. Introduction of, or replacement by, carbonates.

b. See: carbonation.

carbon bit

A diamond bit in which thc cutting medium is inset carbon.

carbon brick

Brick usually made from crushed coke and bonded with pitch or tar.

carbon dating

See: carbon-14 dating.

carbon diamond

See: carbonado.

carbon dioxide

a. Heavy, colorless; irrespirable gas; CO (sub 2) ; it extinguishes a flame. It is formed in mine explosions and in mine fires and forms part of the afterdamp.

b. Product of complete combustion of carbon fuels. Transported in liquid form in steel cylinders. Used in gaseous form as a fire extinguisher and in solid form as dry ice.

carbon dioxide blasting

A method of blasting coal that has been undercut, topcut, or sheared. Into one end of a seamless high-grade molybdenum-steel cylinder 2 to 3 in (5.08 to 7.62 cm) in diameter and 36 to 60 in (91.44 to 152.4 cm) long is put a cartridge containing a mixture of potassium perchlorate and charcoal with an electric match. The other end is sealed by a metal disk weaker than the shell and held in place by a cap that has holes at about 45 degrees to the axis of the cylinder. The cylinder is filled with liquid carbon dioxide at a pressure of 1,000 psi (6.9 MPa) and inserted in a borehole with the cap holes pointing outward. The heating mixture is lit and raises the gas pressure so that the disk is sheared; the carbon dioxide escaping through the angular holes tends to hold the cylinder in place, and break and push the coal forward. If the gas pressure is not enough to break the coal, the cylinder, if not properly set, will be blown from the borehole. The cylinder can be used over and over. It is claimed that a greater portion of lump coal is obtained than with ordinary explosives. Some smelters loosen slag in the same way.

carbon-hydrogen ratio

A method of classifying coals by determining the ratio that exists between the carbon and hydrogen present in them. Thus, if a given coal contains 80% carbon and 5% hydrogen, the C/H ratio would be 80:5, or 16. Bituminous coals have a C/H ratio between 14 and 17, and most anthracites have a ratio between 24 and 29. Abbreviation: C/H ratio. See also: anthracite.

Carboniferous

The Mississippian and Pennsylvanian periods combined, ranging from about 345 million years to about 280 million years ago; also, the corresponding systems of rocks. In European usage, the Carboniferous is considered as a single period and is divided into upper and lower parts. The Permian is sometimes included.

carbonification

Carbonification is the process by which the vegetable substances of peat were transformed in the partial absence of air and under the influence of temperature and pressure throughout geological time into lignite and subsequently into coal. See also: coalification.

carbon-in-leach process

A process step wherein granular activated carbon particles much larger than the ground ore particles are introduced into the ore pulp. Cyanide leaching and precious metals adsorption onto the activated carbon occur simultaneously. The loaded activated carbon is mechanically screened to separate it from the barren ore pulp and processed to remove the precious metals and prepare it for reuse.

carbon-in-pulp leaching

A precious metals leaching technique in which granular activated carbon particles much larger than the ground ore particles are added to the cyanidation pulp after the precious metals have been solubilized. The activated carbon and pulp are agitated together to enable the solubilized precious metals to become adsorbed onto the activated carbon. The loaded activated carbon is mechanically screened to separate it from the barren ore pulp and processed to remove the precious metals and prepare it for reuse.

carbonite

a. A native coke, occurring at the Edgehill Mines, near Richmond, VA; it is more compact than artificial coke and some varieties afford bitumen.

b. Coal altered by an igneous intrusion. Syn: cokeite. c. Fossil coal. d. Very brittle, black variety of bitumen, infusible and insoluble in organic solvents, containing about 85% carbon and 6% hydrogen. e. A permissible explosive.

carbonitriding

Introducing carbon and nitrogen into a solid ferrous alloy above AC (sub 1) in an atmosphere that contains suitable gases such as hydrocarbons, carbon monoxide, and ammonia. The carbonitrided alloy is usually quench-hardened.

carbonization

a. In the process of coalification, the accumulation of residual carbon by the changes in organic matter and decomposition products. See also: coalification.

b. The accumulation of carbon by the slow, underwater decay of organic matter. c. The conversion into carbon of a carbonceous substance such as coal by driving off the other components, either by heat under laboratory conditions or by natural processes.

carbonizing

The reduction of a substance to carbon by subjecting it to intense heat in a closed vessel.

carbon monoxide

Colorless; odorless; very toxic gas; CO; burns to carbon dioxide with a blue flame. Formed as a product of the incomplete combustion of carbon (such as in water gas and producer gas; in the exhaust gases from internal-combustion engines, such as automotive; and in the gases from the detonation of explosives). Used chiefly in the synthesis of carbonyls (such as nickel carbonyl in the refining of nickel), phosgene, and many organic compounds (such as hydrocarbons for fuels, methanol and higher alcohols, aldehydes, and formates). This gas is formed during mine fires and after explosions.

carbon monoxide poisoning

In diving, this type of accident usually occurs as a result of contamination of the diver's air supply by exhaust gases from an internal-combustion engine.

Carbon oil

Trade name for kerosine.

carbon steel

Steel containing carbon up to about 2% and only residual quantities of other elements except those added for deoxidation, with silicon usually limited to 0.60% and manganese to about 1.65%. Also called plain carbon steel; ordinary steel; straight carbon steel.

carbon trash

Carbon remains of plant life found in sedimentary strata and often associated with uranium and red-bed copper mineralization.

carbopyrite

Any coal microlithotype containing 5% to 20% by volume of iron disulfide (pyrite and marcasite).

Carborundum

Trade name for green, often iridescent, artificial carbon silicide, CSi. Hexagonal-rhombohedral plates. It is produced in an electric furnace and used as an abrasive and as a refractory material. Is useful for sharpening tools. Identical with moissanite. See also: moissanite.

carboxylic acid method

In flotation, a method for treatment of various oxygen ores using carboxylic acids as collectors with gangue depressants to float base-metal minerals from associated impurities. The process is suitable for processing apatite (phosphate), carbonates or oxides of lead, copper, or zinc; somewhat less useful with other lead minerals and with hemimorphite; and unsuitable for chrysocolla.

carbozite

A black liquid, made from a bituminous ore, used for the protection of steel surfaces during transport and storage. This fluid dries rapidly to a hard gloss, which is resistant to acids, alkalies, moisture, sea air, and temperatures up to 200 degrees C.

carburan

a. A hydrocarbon related to, or identical with, thucholite, the ash of which contains uranium, lead, and iron.

b. A variety of anthraxolite, from pegmatites of Karelia, former U.S.S.R.

carbureted hydrogen

An odorless, flammable gas, CH (sub 4) . Known in coal mines as combustible gases or gas. See also: methane.

carburization

The process of imparting carbon, such as in making cement steel.

carburizing

Hard-surfacing of steel by heating above the critical temperature in an inert atmosphere with a source of carbon (e.g., cyanide salts), thus forming a cementite casing above a tough core (which has already been machined).

carburizing flame

A gas flame that will introduce carbon into some heated metals such as during a gas welding operation. A carburizing flame is a reducing flame, but a reducing flame is not necessarily a carburizing flame.

carcass

The tension-carrying portion of a conveyor belt. It may be composed of multiple plies of fabric or cord, and simple layers of cord or steel cable, bonded together with rubber.

car chalker

In bituminous coal mining, a laborer who chalks on a car the number of rooms or working places from which coal is obtained in order that a production record of all parts of a mine can be maintained.

card concentrator

A table made of two planes having a flexible joint between them dividing the table into two nearly equal triangles, forming a diagonal line along which concentrates separate from the tailings.

cardinal point

a. One of the four principal "points" of a compass.

b. A change in the speed of the ropes on a winding drum, which occurs at certain definite intervals during the winding cycle.

Cardox

Trade name for an explosive device used principally in coal mining. See also: carbon dioxide blasting.

cardoxide

A baked mixture of caustic soda and lime, used in the container or regenerator of self-contained mine-rescue or oxygen-breathing apparatus to absorb the exhaled carbon dioxide. It has an advantage over straight caustic soda in that it does not cake, liquefy, or solidify when used.

Cardox-plant operator

In bituminous coal mining, one who recharges steel shells (tubes) known by the trade name Cardox with metal shearing disks, electrical firing elements, and liquid carbon dioxide to prepare them for blasting coal.

Cardox shell

Steel shell used in carbon dioxide blasting.

car dropper

See: car runner.

card table

A shaking table with a grooved deck instead of nailed-on riffles. Used in gravity concentration of sands.

card tender

In the asbestos products industry, one who tends a carding machine that cleans asbestos, cotton, or other fibers; arranges fibers parallel; and transforms them from a roll or lap into a ropelike untwisted strand of cotton (sliver). Also called allye tender; card feeder; card hand; card operator; winder.

car dump

See: tipple.

car dumper

a. A mechanical device for tilting a railroad hopper or gondola car over sidewise and emptying its contents.

b. A person who unloads cars by upending or overturning them.

card weight pipe

A term used to designate standard or full weight pipe, which is the Briggs standard thickness of pipe.

car filler

See: mucker.

car haul

A pusher chain conveyor used for moving small cars, such as mine cars, along a track. A form of tow conveyor.

caries texture

In ore microscopy, a replacement pattern in which the younger mineral forms a series of scallop-shaped incursions into the host mineral, which resemble filled dental cavities.

carinate fold

In geology, an isoclinal fold. See also: isocline.

Carinthian process

A metallurgical method for treating lead ore, the characteristics of which are the smallness of the charge; the slow roasting, so that for every part of lead sulfide one part of sulfate and at least two parts of oxide are formed; the low temperature at which all of the operations are carried on; and the aim to extract all the lead in the reverberatory. The hearth is inclined toward the flue, and the lead is collected outside the furnace. Syn: Corinthian process.

car loader

See: loader; chute loader; boxcar loader; loading conveyor.

Carlsbad twin

A twinned crystal in which the twinning axis is the c axis, the operation is a rotation of 180 degrees , and the contact surface is parallel to the side pinacoid; common in the alkali feldspars. Also spelled Karlsbad twin.

carman

A worker who handles mine or railroad cars at a mine. May be designated according to job, such as brakeman; car cleaner; car pincher; car runner; pusher. Also called car handler.

Carmichel-Bradford process

See: blast roasting.

carminite

A carmine to tile-red lead-iron-arsenate, perhaps Pb (sub 3) As (sub 2) O (sub 8) .10FeAsO (sub 4) . Found in clusters of fine needles; also in spheroidal forms.

carn

See: cairn.

carnallite

An orthorhombic mineral, KMgCl (sub 3) .6H (sub 2) O ; milk-white to reddish; a saline residue.

carnallite plant operator

In ore dressing, smelting, and refining, one who makes carnallite flux used in magnesium refining--by weighing carnallite ingredients according to formula and mixing them thoroughly, using a shovel. The mixture is then melted in a furnace crucible and poured into cooling pans.

carnegieite

A triclinic and isometric compound, NaAlSiO (sub 4) ; a high-temperature polymorph of nepheline.

carnelian

A translucent pale to deep- or orange-red variety of chalcedony containing iron impurities. CF: sard. Also spelled cornelian. Syn: carneol.

carneol

See: carnelian.

car nipper

See: car runner.

carnotite

A monoclinic mineral 2 ; bright yellow to lemon- and greenish-yellow; strongly radioactive; commonly occurs mixed with tyuyamunite; widespread in Colorado, Utah, New Mexico, and Arizona; occurs chiefly in crossbedded sandstones of Triassic or Jurassic age, either disseminated or as relatively pure masses around petrified or carbonized vegetal matter. Secondary in origin, having been formed from the action of meteoritic waters on preexisting uranium minerals; a source of uranium and radium. Syn: yellow ore.

carpholite

An orthorhombic mineral, MnAl (sub 2) Si (sub 2) O (sub 6) (OH) (sub 4) ; in yellow laths elongated in the c direction with prismatic cleavage at 68.5 degrees .

car pincher

In anthracite, bituminous, and metal mining, a laborer who moves railroad cars into position directly under loading chutes at a breaker or tipple, inserting a pinch bar under the car wheels and bearing down or pulling up on it to force the car forward. Also called car shifter; car spotter; railroad-car shifter; spotter.

carrack

Eng. See: capel.

Carrara marble

Any of the marbles quarried near Carrara, Italy. The prevailing colors are white to bluish, or white with blue veins; a fine grade of statuary marble is included.

car retarder

a. An appliance for reducing or controlling the speed of mine cars.

b. A car retarder consists of a brakeshoe located along the track. On an electrical impulse, it is forced against both sides of the car wheels by compressed air. Control can be manual or automatic. Used to control the speed of railroad cars in industrial yards.

carriage

a. A term used with shaker conveyor supports. Carriages may be designated as ball-frame, wheel, or roller carriages, depending on their construction. The carriage may or may not be attached solidly to the conveyor troughs. See also: slope cage.

b. See: cage. c. A sliding or rolling base or supporting frame.

carriage mounting

One or more rock drills mounted on a wheeled frame; used in tunneling.

Carribel explosive

A permitted explosive of medium strength, which can be used in wet boreholes provided its immersion time does not exceed 2 to 3 h. Can be used for coal and ripping shots in conjunction with short-delay detonators.

carrier

a. A rotating or sliding mounting or case.

b. Container traveling on an aerial ropeway.

carrollite

An isometric mineral, Cu(Co,Ni) (sub 2) S (sub 4) ; linnaeite group. Formerly called sychnodymite.

carrousel conveyor

A continuous platform or series of spaced platforms that move in a circular horizontal path.

car runner

In anthracite and bituminous coal mining, a laborer who runs cars down inclined haulageways from working places to switches or sidings at the shaft or along main haulageways. A runner may be designated according to material hauled, such as culm runner or rock car runner. Syn: car dropper; car nipper; dropper; load dropper; runner.

carry

a. Scot. The thickness of roof rock taken down in working a seam.

b. The thickness of seam that can be conveniently taken down at one working.

carryall

A self-loading carrier device with a scraperlike, retractable bottom; usually self-propelled and used esp. for excavating and hauling unconsolidated or crushed rock and earthy materials. See also: scraper.

Carryall

Trade name for a LeTourneau-Westinghouse scraper.

carryall scraper

See: carryall.

carrying belt

The belt on which coal or ore is transported to the discharge point. The carrying belt is the upper strand except in the case of a bottom belt conveyor. See also: carrying run.

carrying gate

Derb. The main haulage road in a mine.

carrying idler

a. In belt conveyors, one of the belt idlers upon which the load-carrying portion of belting is supported.

b. In live roller conveyors, the roll upon which the load is supported while being conveyed.

carrying roller

The conveyor roll upon which the conveyor belt or the object being transported is supported.

carrying run

That portion of a conveyor in or on which material is conveyed. See also: carrying belt.

car slide

The ramped loading platform for a scraper loader.

car spotter

A term used for the small hoist employed to haul a trip of empty cars under the loading end of a gathering conveyor or elevator. Also called tugger. See also: car pincher.

car stop

A contrivance to arrest the movement of a mine car.

cartographic

Of or pertaining to a map. A cartographic unit in geology is a rock or a group of rocks that is shown on a geologic map by a single color or pattern.

cartography

The art of map or chart construction, and the science on which it is based. It includes the whole series of map-making operations, from the actual surveying of the ground to the final printing of the map.

cartology

A graphic method of coal-seam correlation, involving the mapping and drawing of both vertical and horizontal sections.

carton

A lightweight inner container for explosive materials, usually encased in a substantial shipping container called a case.

cartridge

a. An individual closed shell, bag, or tube of circular cross section containing explosive material.

b. A cylindrical, waterproof, paper shell, filled with high explosive and closed at both ends, that is used in blasting. c. A cylindrical, waterproof, paper shell filled with cement or other material used in plugging or sealing cavities or cavey ground encountered in drilling a borehole. See also: plug. d. Cylinder--about 4 in (10 cm) long and 2-1/2 in (6.4 cm) in diameter--of highly compressed caustic lime made with a groove along the side, used in breaking down coal. e. A single pellet of explosive, which may be 4 oz or 8 oz (113.4 g or 226.8 g).

cartridge count

The number of cartridges in a standard case, which typically contains about 50 lb (22.7 kg) of explosive material.

cartridge fuse

A fuse enclosed in an insulating tube in order to confine the arc when the fuse blows.

cartridge punch

A wooden, plastic, or non-sparking metallic device used to punch an opening in an explosive cartridge to accept a detonator or a section of detonating cord.

cartridge strength

A rating that compares a given volume of explosive with an equivalent volume of straight nitroglycerin dynamite, expressed as a percentage. Syn: bulk strength.

car-type conveyor

A series of cars attached to and propelled by an endless chain or other linkage running on a horizontal or slight incline.

car whacker

See: mine-car repairman.

Casagrande liquid limit apparatus

An appliance to determine the liquid limit of a soil. It consists of a brass dish, handle, and cam mounted on a hard rubber base. The dish falls through a distance of 1 cm per rotation. A sample of soil 1 cm thick is placed in the dish with a groove 11 mm wide at the top and 2 mm at the bottom. The number of jars required to cause the 2-mm gap to close along 1/2 in (12.7 mm) is recorded.

cascade coal dryer

A thermal process for drying fine coal. An example of this type is the Conreur dryer. Coal entering the top of the drying tower is carried down by a series of rollers, being permeated by an ascending stream of hot air. Fixed baffles direct the air to facilitate mingling. The very finest particles may have to be recovered by dry filters or wet scrubbers. The dryer treats coal with a top size ranging from 1/4 to 2 in (0.64 to 5.08 cm). See also: fluidized bed dryer; thermal drying.

cascade control

Externally impressed signal series that connects several controllers or resetting devices in series.

cascade flotation cell

Elementary type of flotation cell in which air is entrained by a plunging cascade of pulp; mineralized bubbles are removed farther downstream.

cascade upgrading

See: countercurrent decantation.

cascading

Movement of crop load in a ball mill rotating at such a speed that the balls breaking free at the top of the rising load roll quietly down to the toe of the charge. With increased peripheral speed, motion changes to turbulent cataracting and, still faster, to avalanching when the upper layer of crushing bodies breaks clear and falls freely to the top of the crop load.

cascadite

A sodic minette containing biotite, olivine, and augite phenocrysts in a groundmass composed almost entirely of alkali feldspar. Principally a dike rock.

case

a. A small fissure, admitting water into the mine workings.

b. One of the frames, of four pieces of plank each, placed side by side to form a continuous lining in galleries run in loose earth. c. To line a borehole with steel tubing, such as casing or pipe. Syn: case in. See also: blankoff. d. In a ferrous alloy, the outer portion that has been made harder than the inner portion, or core, by casehardening.

cased

A borehole lined with some form of steel tubing, such as casing or pipe. See also: case off.

cased off

See: case off.

casehardening

a. The geological process by which the surface of a porous rock, esp. a sandstone or a tuff, is coated by a cement or a desert varnish; formed by the evaporation of a mineral-bearing solution.

b. Hardening a ferrous alloy so that the outer portion, or case, is made substantially harder than the inner portion, or core. Typical processes used for casehardening are carburizing, cyaniding, carbonitriding, nitriding, induction hardening, and flame hardening.

case in

See: case.

case liner

A plastic or paper barrier used to prevent the escape of explosive materials from a case.

case off

To line a borehole with some form of steel tubing to prevent entry of broken rock materials, gas, or liquids into the borehole. Also called blank off; case. See also: blankoff.

cash

Som. Soft shale or bind in coal mines.

casing

a. Special steel tubing welded or screwed together and lowered into a borehole to prevent entry of loose rock, gas, or liquid into the borehole, to prevent loss of circulation liquid into porous, cavernous, or crevassed ground, and to support the sides of a borehole. See also: tubing; flush-joint casing.

b. The large-diameter pipe cemented in the hole, such as surface casing, protective casing, and production casing. c. Process of inserting casing in a borehole. d. A structure of wood, metal, or other material that completely encloses the elevating or conveying machinery elements to support them; to afford safety protection; to protect from the weather; to confine dust, gases, or fumes arising from the material being conveyed; or to form a part of the conveyor in the same manner as a trough. e. A zone of material altered by vein action and lying between the unaltered country rock and the vein. f. A term applied to thin slabs of sandstone that split out between closely spaced joints. g. The steel lining of a circular shaft. See also: conduit.

casing catcher

A safety device equipped with slips or dogs to catch and grip casing if it is dropped while being lowered into or lifted from a borehole. Also miscalled tubing catcher; tubing hanger.

casing clamp

A mechanical device designed to facilitate the hoisting or suspension of casing in a borehole. Made by forming a half circle in a heavy steel bar. When bolted together, in pairs, the bars fit around the outside and tightly grip the casing. The size of the clamp is determined by the outside diameter of the casing to be handled. See also: pipe clamp.

casing dog

a. A lifting device consisting of one or more serrated sliding wedges working inside a cone-shaped collar. Used to grip and hold casing while it is being raised or lowered into a borehole. See also: bulldog; dog.

b. A fishing tool.

casing float

A rubber-ball-type check valve, generally placed near the bottom of a long string of casing. Its use reduces the load imposed on the hoisting mechanism in lowering casing into a wet borehole. Also called casing valve; float valve.

casing off

Process of inserting a line of casing into a borehole. See also: case; case off.

casing point

In borehole drilling, the depth to which the casing is entered.

casing pressure

The pressure built up in the casing when closed at the top of the well. It is usually measured by placing a pressure gage on one of the side outlets on the casing head.

Cassel brown

A brown earthy substance found in peat and lignite beds and used as a pigment; originally found near Cassel, Germany. Cologne brown or Cologne earth is a similar substance originally found near Cologne, Germany.

cassiterite

A tetragonal mineral, 4 ; rutile group; adamantine; reddish brown to black; forms prismatic crystals, or massive concentric fibrous structure (wood tin); sp gr, 7.03; occurs in veins associated with granite and granite pegmatite, or placers (stream tin); a source of tin. Syn: tin stone; tin spar; tin ore; black tin.

cast

a. Secondary rock or mineral material that fills a cavity formed by the decay or dissolution of some or all of the original hard material. CF: mold.

b. A sedimentary structure representing the infilling of an original mark or depression made on top of a soft bed and preserved as a solid form on the underside of the overlying and more durable stratum; e.g., a flute cast or a load cast. Syn: counterpart.

castable

A refractory mix containing heat-resistant, hydraulic setting cement. A refractory concrete.

castable refractory

a. A refractory aggregate that will develop structural strength by hydraulic set after having been tempered with water and compacted.

b. A mixture of a heat-resistant aggregate and a heat-resistant hydraulic cement; for use, it is mixed with water and rammed or poured into place.

cast-after-cast

Corn. The throwing up of ore from one platform to another successively. See also: shamble.

castanite

A former name for hohmannite, Fe (super +3) (sub 2) (SO (sub 4) ) (sub 2) (OH) (sub 2) .7H (sub 2) O .

cast bit

A drill bit in which the diamond-set crown is formed on a bit blank by pouring molten metal into a prepared mold. Also called cast-set bit; cast-metal bit.

cast booster

A cast, extruded or pressed, solid high explosive used to detonate less sensitive explosive materials.

casthouse

A building in which pigs or ingots are cast.

castillite

An impure variety of bornite, containing zinc, lead, and silver sulfides.

casting

a. An object at or near finished shape obtained by solidification of a substance in a mold.

b. Pouring molten metal into a mold to produce an object of desired shape. c. A process of shaping glass by pouring hot glass into molds or onto tables or molds. See also: teemer. d. A process for forming ceramic ware by introducing a body slip into a porous mold that absorbs sufficient water (or other liquid) from the slip to produce a semirigid article.

casting machine

A series of iron molds on an endless-belt conveyor to receive and cast molten pig iron into form as it comes from a furnace.

casting over

a. A quarryman's term for an operation consisting of making a cut with a steam shovel, which, instead of loading the material on cars, moves it to one side, forming a long ridge.

b. The operation of reestablishing benches that have been covered or caved, and also cutting up a high bank into one or more smaller banks.

casting pit

The space in a foundry in which molds are placed and castings are made. In the Bessemer and open-hearth steelworks, it is the space utilized for casting the molten steel into cast iron ingot molds.

castings

One of several terms (and/or letter symbols) commonly used to designate low-quality drill diamonds.

casting shrinkage

a. Liquid shrinkage--the reduction in volume of liquid metal as it cools to the liquidus.

b. Solidification shrinkage--the reduction in volume of metal from the beginning to ending of solidification. c. Solid shrinkage--the reduction in volume of metal from the solidus to room temperature. d. Total shrinkage--the sum of the shrinkage in definitions a, b, and c above.

casting strain

Strain in a casting caused by casting stresses that develop as the casting cools.

casting stress

Stress set in a casting because of geometry and casting shrinkage.

casting wheel

A large turntable with molds mounted on the outer edge. Used primarily in the base metal industries for cast ingots, anodes, etc.

casting-wheel operator

In ore beneficiation, smelting, and refining, one who operates a large rotating casting wheel to pour molten, nonferrous metal, such as copper or lead, into molds mounted on the edge of the wheel.

cast iron

Iron containing carbon in excess of its solubility in the austenite that exists in the alloy at the eutectic temperature. For the various forms--gray cast iron, white cast iron, malleable cast iron, and nodular cast iron--the word "cast" is often left out, resulting in the terms gray iron, white iron, malleable iron, and nodular iron, respectively.

castor

See: castorite.

castor amine

An oil. Used in ore flotation as a selective collector and in rustproofing metal surfaces.

castorite

a. A natural, colorless silicate of lithium and aluminum.

b. A transparent variety of petalite. Syn: castor.

cast primer

a. A cast unit of explosive commonly used to initiate detonation in a blasting agent.

b. A cast unit of explosive, usually pentolite or composition B; commonly used to initiate detonation in a blasting agent.

cast steel

Steel as cast; i.e., not shaped by mechanical working. Originally applied to steel made by the crucible process as distinguished from that made by cementation of wrought iron.

cata-

A prefix to indicate that the rock belongs to the deepest zone of metamorphism, which is characterized by very high temperature, hydrostatic pressure, and relatively low shearing stress. CF: epi-; meta-; meso-. Syn: kata-.

cataclasis

Rock deformation accomplished by fracture and rotation of mineral grains or aggregates without chemical reconstitution.

cataclasite

A cataclastic rock that has been formed by shattering (or cataclasis), which has been less extreme than in mylonite. See also: augen gneiss; crush breccia; mylonite; mylonite gneiss.

cataclastic

a. Pertaining to the structure produced in a rock by the action of severe mechanical stress during dynamic metamorphism; characteristic features include the bending, breaking, and granulation of the minerals. Also said of the rocks exhibiting such structures. See also: mortar structure.

b. Pertaining to clastic rocks, the fragments of which have been produced by the fracture of preexisting rocks by Earth stresses; e.g., crush breccia. Syn: kataclastic. CF: autoclastic.

cataclysm

a. Any geologic event that produces sudden and extensive changes in the Earth's surface; e.g., an exceptionally violent earthquake. Syn: cataclysmic; cataclysmal.

b. Any violent, overwhelming flood that spreads over the land; a deluge.

cataclysmal

See: cataclysm.

cataclysmic

See: cataclysm.

catalysis

Acceleration or deceleration of a chemical reaction produced by a substance that is unchanged by the reaction.

catalyst

A substance capable of changing the rate of a reaction without itself undergoing any net change.

catalytic methanometer

A combustible-gases detector depending upon the combustion or oxidation of methane at heated filaments. Usually the gas is drawn through the apparatus by a rubber suction bulb, and the filaments are heated by a battery in the instrument. A version of this principle is the resistance methanometer.

catalytic oxidation

A process that converts the incompletely burned hydrocarbons present in fuel exhaust into harmless gases. It involves burning up the fuel remnants with the aid of catalysts-- chemical agents, such as platinum and palladium, that speed up reactions without being consumed themselves.

cataphoresis

Movement of charged particles in a fluid medium in response to an electric field. Metallic hydroxides and other positive sols migrate to the cathode and negatives ones to the anode. See also: electrophoresis.

catapleiite

A hexagonal mineral, Na (sub 2) ZrSi (sub 3) O (sub 9) .2H (sub 2) O ; yellow to yellow-brown; forms thin, tabular hexagonal prisms.

catarinite

An obsolete term for an iron meteorite remarkable for a high proportion of nickel.

catastrophe

In geology, a sudden, violent change in the physical conditions of the Earth's surface; a cataclysm.

catch

a. Projection in a mine shaft that arrests a cage, skip, or other reciprocating system in the event of fracture or overwind.

b. One of the catches or rests placed on shaft timbers, to hold the cage when it is brought to rest at the top, bottom, or any intermediate landing. See also: chair; dog; wing; rests. c. In coal work, a device for holding trams in a cage when hoisting. See also: jack catch. d. One of the stops fitted on a cage to prevent cars from running off.

catcher

See: core lifter.

catch gear

An appliance fixed in the headgear to limit the drop of a cage after an overwind. The upward speed and momentum of the loaded cage (after its release from the rope) may be such that its subsequent drop is so severe as to fracture the suspension gear, resulting in the cage falling down the shaft. The amount of drop is limited by the catch gear, which consists of a series of catches suspended from beams supported on hydropneumatic buffers to reduce the impact shock. The cage is released by raising it slightly and retracting the catches. See also: detaching hook; overwind.

catchment area

a. The recharge area and all areas that contribute water to it.

b. An area paved or otherwise waterproofed to provide a water supply for a storage reservoir. See also: drainage basin. Syn: gathering ground.

catch pit

a. In mineral processing, a sump in a mill to which the floor slopes gently, and into which all spillage gravitates or is hosed either for return by pumping to its place in the flowline or for periodical removal. Also called catch sump.

b. See: sump; tailing pit.

catch point

a. One of a set of spring-loaded points in an upgrade railway line that close behind a rising train. If any rolling stock breaks away it is then automatically diverted to a siding.

b. Position of intersection of a road cut or fell with natural ground; usually marked with a stake.

catch prop

Prop erected in the face to act as a temporary support until permanent supports are brought forward. Also called watch prop; safety prop.

catch scaffold

Eng. A platform in a shaft a few feet beneath a working scaffold; to be used in case of accident.

catchwater drain

A surface drain to intercept and collect the flow of water from adjoining land, so as to prevent it from reaching a road or mine sidings. See also: subsoil drainage.

cat claw

A miner's term applied locally in Illinois to a bed of marcasite from 2 to 6 in (5.08 to 15.24 cm) thick that sometimes occurs between the "clod" roof of a coal seam and the more stratified shale above. The lower surface of the marcasite bed is characterized by very irregular protuberances extending downward 1 to 3 in (2.54 to 7.62 cm) into the clod. Also called cat.

cat dirt

a. Derb. A hard fireclay.

b. Derb. Coal mixed with pyrite.

catear

Sp. To search for new mines; to prospect.

catenary suspension

The overhead suspension of contact wire for electric traction by vertical links of different lengths connected to a catenary wire above it. The contact wire will thus be maintained at a constant height.

caterpillar

An endless chain of plates that functions as a wheel for heavy vehicles. See also: crawler track.

caterpillar chain

A short endless chain on which dogs or teeth are spaced to mesh with and move or be moved by a conveyor chain.

caterpillar chain dog

A dog or tooth attached to a "caterpillar chain" to provide the driving contact with the conveyor chain.

caterpillar drive

A drive equipped with a "caterpillar chain" that engages and propels the "conveyor chain."

catfaced block

In New York and Pennsylvania, a bluestone quarryman's term for a mass of waste situated between two closely spaced open joints.

cathead sheave

A sheave set on the topmost part of a pile frame.

cathode

The electrode where electrons enter, or current leaves, an operating system, such as a battery, an electrolytic cell, an X-ray tube, or a vacuum tube. In the first of these, the cathode is positive; in the other three, negative. In a battery or electrolytic cell, it is the electrode where reduction occurs. Opposite of anode. See also: electrode.

cathode compartment

In an electrolytic cell, the enclosure formed by a diaphragm around the cathode.

cathode copper

Electrolytically refined copper that has been deposited on the cathode of an electrolytic bath of acidified copper sulfate solution. Such copper is usually remelted in a furnace before being marketed as electrolytic copper.

cathode efficiency

Current efficiency at a cathode.

cathode film

The portion of a solution in immediate contact with the cathode during electrolysis.

cathodic corrosion

Corrosion of the cathodic member of a galvanic couple resulting from the flow of current.

cathole

A local term used in southern Michigan for a shallow boggy depression less than 1 acre (0.4 ha) in extent, esp. one formed by a glacier in a till plain.

catholyte

The electrolyte adjacent to the cathode in an electrolytic cell.

cation

a. An ion having a positive charge.

b. Any positive ion; named for its attraction to the cathode or negative terminal of an electrolytic cell. CF: anion.

cation exchange

The displacement of a cation bound to a site on the surface of a solid, such as in silica-alumina clay-mineral packets, by a cation in solution. Syn: base exchange. See also: ion exchange.

cationic collector

In flotation, an amine or related organic compound capable of producing positively charged hydrocarbon-bearing ions (hence the name cationic collector) for the purpose of floating miscellaneous minerals, including silicates.

cationic detergent

A detergent in which the cation is the active part.

cationic reagent

In flotation, a surface-active substance that has the active constituent in the positive ion. Used to flocculate and to collect minerals that are not flocculated by the reagents, such as oleic acid or soaps, in which the surface-active ingredient is the negative ion. Reagents used are chiefly the quaternary ammonium compounds; e.g., cetyl trimethyl ammonium bromide.

catlinite

A hard red clay found in southwestern Minnesota, formerly used by the Dakota Native Americans for making tobacco pipes. Named after George Catlin (1796-1872), American painter. Syn: pipestone.

catogene

Pertaining to sedimentary rocks, signifying that they were formed by deposition from above, as of suspended material.

cat run

A low passage that requires crawling to traverse it. Syn: crawlway.

cat's-eye

a. Any gemstone that, when cut en cabochon, exhibits under a single strong point source of light a narrow, well-defined chatoyant band or streak that moves across the summit of the gemstone, shifts from side to side as it is turned, and resembles a slit pupil of the eye of a cat. Internal reflection of light from parallel inclusions of tiny fibrous crystals or from long parallel cavities or tubes causes the cat's-eye.

b. Alternate term for tiger's-eye, the silicified form of crocidolite asbestos; sometimes polished and used as ornaments. c. A greenish gem variety of chrysoberyl that exhibits chatoyancy. Syn: cymophane; oriental cat's-eye. d. A variety of minutely fibrous, grayish-green quartz (chalcedony) that exhibits an opalescent play of light. Syn: occidental cat's-eye. e. A yellowish-brown silicified variety of crocidolite. CF: tiger's-eye. The term used alone properly applies only to (c).

catskinner

Operator of a crawler tractor.

Cattermole Process

An early flotation process (1903) based on adhesion of sulfide minerals to oil. Mineral oil or fatty acid agglomerated heavy minerals into floccules, which were separated by classification from overflowing gangue.

catty

a. Any of various units of weight used in China and southeast Asia varying around 1-1/3 lb or 600 g; also, a Chinese unit according to a standard set up in 1929 equal to 1.1023 lb or 500 g.

b. A gold weight that equals 2.9818 troy pounds (1.1129 kg).

catwalk

A pathway, usually of wood or metal, that gives access to parts of large machines.

cauk

See: cawk.

cauldron

An inclusive term for all volcanic subsidence structures regardless of shape or size, depth of erosion, or connection with the surface. The term thus includes cauldron subsidences, in the classical sense, and collapse calderas. See also: caldera.

cauldron subsidence

The sinking of part of the roof of an intrusion within a closed system of peripheral faults into which magma has penetrated, often to form ring dikes. See also: subsidence.

cauliflowering

The tendency of coal to swell and open out when heated, thus exposing a surface out of all proportion to the size of the original coal. See also: swelling number.

caunche

In coal mining, removal of part of the roof or floor to increase the height of a roadway. Also spelled canch.

caustic

Capable of destroying the texture of anything or eating away its substance by chemical action; burning; corrosive.

caustic ammonia

Gaseous or dissolved ammonia.

caustic embrittlement

Effect on metal of immersion in caustic alkaline solutions.

caustic soda

Sodium hydroxide, NaOH; deliquescent; a soapy feel; its solution in water is strongly alkaline. The molten caustic dissolves such materials as enamels, sand, or glass, which contain a high percentage of silica.

caustobiolite

A general name for a fossil combustible substance. Syn: caustolith.

caustobiolith

This term designates a rock with a fairly high content of organic carbon compounds or even pure carbon where the latter is, like the carbon compounds, of organic origin.

caustolith

A rock that has the property of combustibility (Grabau). It is usually of organic origin (e.g., coal and peat), but inorganic deposits (e.g., sulfur, asphalt, and graphite) also occur. See also: caustobiolite.

caustophytolith

A caustobiolith formed by the direct accumulation of vegetal matter; e.g., peat, lignite, and coal.

cave

a. Fragmented rock materials, derived from the sidewalls of a borehole, that obstruct the hole or hinder drilling progress.

b. To allow a mine roof to fall without retarding supports or waste packs. c. A falling in of the roof strata, sometimes extending to the surface and causing a depression therein. Also called cave-in. d. The partial or complete failure of borehole sidewalls or mine workings. e. Collapse of an unstable bank. f. A natural cavity, recess, chamber, or series of chambers and galleries beneath the surface of the Earth, within a mountain, a ledge or rocks, etc.; sometimes a similar cavity artificially excavated. See also: cavity.

caved stope

There are two distinct types of caved stopes. In the first, the ore is broken by caving induced by undercutting a block of ore. In the second, the ore itself is removed by excavating a series of horizontal or inclined slices, while the overlying capping is allowed to cave and fill the space occupied previously by the ore. The first type comprises the caving methods of mining, while the second comprises the top-slicing method.

cave hole

A depression at the surface, caused by a fall of the roof in a mine.

cave-in

Collapse of the walls or roof of a mine excavation.

cave-in-heave

The partial or complete collapse of the walls of a borehole.

cave line

A linear area inby the last solid ground, in a longwall-type mine, where the roof or back caves behind the retreating excavation.

cave marble

See: cave onyx.

cave onyx

A compact banded deposit of calcite or aragonite found in caves, capable of taking a high polish and resembling true onyx in appearance. See also: dripstone; onyx marble; travertine. Syn: cave marble.

caver

a. Eng. A thief who steals ore or coal at a mine.

b. The officer appointed to guard a mine. c. A person whose hobby is exploring caves. Also called a spelunker.

cavernous

Said of an area or geologic formation, such as limestone, that contains caverns, or caves. Said of the texture of a volcanic rock that is coarsely porous or cellular.

cavil

a. To draw lots at stated periods--by miners to determine the places in which they will work for the following period.

b. A type of heavy sledge with one blunt and one pointed end. Used for rough shaping stone at a quarry.

caving

a. A stoping method in which ore is broken by induced caving. This may be achieved by (1) block caving, including caving to main levels and caving to chutes or branched raises; or (2) sublevel caving. See also: stope.

b. In coal mining, the practice of encouraging the roof over the waste to collapse freely so that it fills the waste area, thereby avoiding the need to pack. In metal mining, caving implies the dropping of the overburden as part of the system of mining. See also: block caving; sublevel caving; top slicing. c. The failure and sloughing in of sidewalls of boreholes, mine workings, or excavations. d. Fall of rock underground. See also: cavings.

caving by raising

See: chute caving.

caving ground

Rock formations that will not stand in the walls of an underground opening without support, such as that offered by cementation, casing, or timber.

caving hole

A borehole in which fragments of the material making up the walls of the hole slough so much that the borehole cannot be kept open without the use of casing or cementation.

cavings

Fragments of borehole wall-rock material that fall into a borehole, sometimes blocking the hole, and which must be washed or drilled out before the borehole can be deepened. See also: caving.

caving system

a. A method of mining in which the support of a great block of ore is removed, allowed to cave or fall, and in falling to be broken sufficiently to be handled; the overlying strata subside as the ore is withdrawn. There are several varieties of the system. See also: block caving; fall; top slicing and cover caving; top slicing combined with ore caving.

b. Longwall coal mining in which excavated space (gob) is left to collapse. See also: sublevel.

caving the back

See: block caving.

cavitation

The formation and instantaneous collapse of innumerable tiny voids or cavities within a liquid subjected to rapid and intense pressure changes. Cavitation produced by ultrasonic radiation is sometimes used to give violent localized agitation. That caused by severe turbulent flow often leads to cavitation damage.

cavitation noise

The noise produced in a liquid by the collapse of bubbles that have been created by cavitation.

cavity

a. A natural underground opening or void, which may be small or large. See also: cave; vug.

b. The bubble formed by a projectile at water entry. c. A void in a bit caused by a bubble of gas entrapped in the matrix material during the manufacturing process.

cavity-filling deposit

A deposition of minerals in a cavity or rock opening.

cawk

a. Eng. Sulfate of barium heavy spar. See also: barite.

b. Scot. Chalk; limestone. Also spelled cauk.

caxas

Walls of a vein; chest.

c axis

a. In crystallography, a symmetrically unique reference vector, oriented vertically by convention. In the monoclinic system, the second setting orients the c axis at the nonorthogonal angle beta to the unique b axis, the diad. In the triclinic system, all axes are unique with the c axis designated by convention. CF: a axis; b axis.

b. One of three orthogonal reference axes, a, b, and c that are used in structural geology. c. To help describe the geometry of a fabric that possesses monoclinic symmetry, the c axis lies in the unique symmetry plane at right angles to a prominent fabric plane; thus in many tectonites the c axis is normal to the schistosity. d. In a kinematic sense, to describe a deformation plan that possesses monoclinic symmetry, such as a progressive shear. Here the c axis lies in the unique symmetry plane and normal to the movement plane. In a progressive simple shear, the c axis lies normal to the shear plane. Syn: c direction.

c direction

See: c axis.

C-D principle

The convergence-divergence principle used in the Frenkel mixer.