Mining Terminology for Your Education



Adit - a horizontal entrance into a mine, i.e. a tunnel
Air Blast - aka Rock Blast - when the host rock, due to built up stresses and pressures from blasting gives way and sends rock debris and shrapnel flying; it sounds like an earthquake
Air Door - a doorway constructed in a drift or crosscut to control ventilation
Air Line - a line carrying compressed air
Air Mover - a megaphone shaped device powered by compressed air used for ventilation and also known as a bazooka
AN/FO Loader - an air driven device that is used to load drill holes with ammonium nitrate blasting agents
Apron - timber or laggin covering between main timbe sets and the ground
Axe - hand tool used for cutting or splitting timbers and also used to pound in spikes and wedges
Back - any sections of rock or concrete hanging above
Back Stope - method of mining where the entire back is blasted down prior to muck removal
Bad Air - air that is unsuitable for humans, i.e. gas contaminated air
Ball Mill - a large circular drum filled with steel balls use to grind ore with a rolling motion
Batter - a timbering word referring to the angles at which timbers are set for the maximum strength and support
Bazooka - see Air Mover
Bells - signals used to control movements of ore and men in the shafts
Bit - usually diamond coated tips attached to the end of drill rods or steel to drill holes in the rock
Bit Knocker - used to remove the bits from drill steel or rods
Bitch Link - used on a slusher, it is a specially fabricated piece of metal with a hole in it that allows it to lock segments of chain
Blocking - pieces of wood used to hold lagging or timber in place or to fill voids between the timber and the ground
Block Signal - a warning light that alerts a motorman that another train is approaching
Blow Pipe - a small diameter pipe attached to an air hose and used to clean out drill holes or cars
B.O. - means bad order, nonfunctional equipment
Boatswain chair - a D-ring chair that miners strap on to get lowered down into an area of the mine not otherwise accessible
Bomb - an explosive charge used to free hangups in ore chutes or stopes
Bootleg - the part of a drillhole that has not been broken by blasting
Bow Saw - a saw used to cut mine timbers
Bubble Gum - a booster for Dupont primers
Bulkhead - a solid or cribbed barrier used to support, close or open large openings
Buzzy - an air dill used to drill holes in the back or hanging wall
Cage - a car used too transport men or equipment in a shaft similar to an elevator
Cager - a person responsible for operating the cages
Cage Tender - same as Cager
Call Signal - a voice system used to call a cage to a certain level
Camel - a dump ramp used for the fifth wheel of a mine car to roll up and dump the contents
Camel Back - same a Camel
Candleholder - a metal or wooden device that holds candles as an underground light source
Cap - an explosive detonator or in timbering a thick timber on top of two upright posts used to support bulkheads or the ground
Cheater - a pipe placed on the end of a wrench to provide more leverage
Choker - a cable sling
Chute - an opening to transport broken rock or muck down one level or more
Chute Lip - a structure for loading muck or ore into a mine car
Clevis - a U shaped device with a pin for attaching another item
Collar - the first level or surface level of a shaft; also the name of the start of a drill hole
Collar Brace - a wooden brace placed between two wooden posts below the cap
Compressor - a machine that provides compressed air for mine equipment
Core Drill - also known as a diamond drill used to provide cylindrical core samples for the geologists to study and determine the direction of the ore body
Conveyor Belt - a rubber coated steel belt used to transport muck or ore
Crib - roof support or timbers or ties laid in alternating crossed layers
Cribbing - a manway chute, i.e. timbers used to construct a manway or chute
Crib Pillars - a pillar made of timber to support the ground above
Crusher - a mechanical device for breaking rock into manageable size
Detonator - a blasting cap used to detonate explosives
Dog Hole - any small opening driven or blasted into the rock
Double Jack - a sledge hammer
Double Spud - a connector with male thread on each end for making air or water connections
Double Connection - same and Double Spud
Drift - a horizontal opening driven into the rock along the bedding plane or vein structure
Dry - a change room for employees
Exhaust - the ventilation air discharged from the mine
Explosives - dynamite, water gel, ANFO or other agents used to blast the rock
Eye Bolt - threaded rod with a loop on one end which is typically used with an expanding shell to secure into a drill hole for slushing
Face - the end of any opening driven into the rock
Fin Hoe - a hoe shaped scraping device used to rake or drag muck
Fire Extinguisher - a container containing a dry chemical or carbon dioxide based fire suppression agent and compressed air
Fire Hose - a 1.5 to 2.5 inch water hose used to extinguish fires
Fish Plate - railroad splice bars used for connecting two rails together
Flat or Timber Truck - equipment used to move timber or materials
Flotation - a method of seperating minerals from waste rock by use of chemicals
Frog - a switch plate that shifts between two sets of rails
Fuse - a safe, waterproof material that contains powder that burns at 40 feet/second used to ignite the main explosives
Goose Neck - a curved pipe attached to an air drill thru which water or air are piped for drill material removal
Grizzly - a series of rails, straps or angle irons placed in parallel or in a crosshatch pattern to prevent oversized rock from passing through to ore cars or other equipment
Guides - special timber used to guide shaft conveyances in the shaft
Head Frame - the structure at the surface of a mine shaft that contains the sheave wheels which allow haulage up and down the shaft
Header or Manifold - valves and fittings on the main water and air lines; also a tunnel that is being advanced or the wood blocks used between a timber cap and the ground
Highgrader - basically a crook; someone that removes minerals from a mine without the owners consent - a thief
Hitch - a notch or ledge carved into the rock to set timber
Hoist - the power unit comprised of a motor and drum assembly which controls the shaft conveyances
Hoisting Rope or Cable - a stranded wire cable that is used to connect the hoist to the conveyances
Hot Wire - a wire carrying electricity into the mine
Ignitor Cord - a slow burning , sparkler type, hot wire that is connected to the ends of fuse to ignite them
Intake - the fresh air ventilation input to the mine workings
Inverted Door - door used above the chute door to prevent spillage
Jack Hammer - a handheld rock drill
Jack Leg or Feed Leg - an air driven rock drill
Jim Crow - a device used to bend railroad track rails
Jumbo - a rock drill mounted carrier used to drive horizontal openings into rock
Kick Brace - a piece of timber going from a sill to a post
Knee Brace - a piece of timber going between two posts
Lacing or Lagging - timber used to divide or block off areas in manways or shafts
Lanyard - a safety rope with hooks on each end
Lead Line - blasting line run from the blasting face to the trunk line
Levels - worked out or working areas of a mine off the shaft or winze; also a tool to used to level objects
Leyner - an air driven rock drill on a shell usually used for drifitng or longholing
LHD - Load, haul and dump self contained vehicle
Longhole - a hole drilled into rock longer than the length of a normal drill steel
Manway - an opening for the express purpose of allowing men to pass from one area to another
Mats - long steel plates bolted into the rock for support
Measuring Pocket - a fixed steel bin that holds only one skip of muck to prevent overloading of the skips
Mesh - chain link wire fencing used to hold up areas of loose ground
Messinger Cable - a steel cable used to hang electrical or ventialtion lines
Mini Blaster - a mechanism used to detonate a small number of blasting caps
Motor - a battery, electric or diesel powered locomotive used to push or pull trains at the mine
Motor Barn - the charging station for battery powered locomotives
Muck - broken rock, ore or waste
Muck Stick - a shovel
Mucker - a machine used to load muck into ore cars
Non-Ell - a nonelectric primer cord
Oiler - a piece of equipment used to lubricate an air motor or air drill parts
Ore Pass - an opening that is used to transport ore by gravity
Pick - a steel tool with points on both ends used to dig
Pickaroon - lightweight half pick used for handling timber
Pillar - a solid block of rock left as support while other rock around it is mined
Pin Hole - a short drill used for installing eye bolts
Portal - the outside entrance of a tunnel
Post - an upright, wooden timber
Powder - a generalized term used for explosives
Powder Magazine - a storage area for explosives
Prill - ammonium nitrate fuel oil blasting agent (ANFO)
Prill Can - a device used to hold and feed prill while charging blast holes
Prill Gun - a device used to charge the blast holes with prill
Primer - a booster or stick of powder with an inserted blasting cap
Primer Cord - a high speed detonating fuse
Primer Magazine - a storage area for detonators
Promotion - a highly organized groups of criminals that work together constantly changing company names and extracting money from unwitting investors
Pull Bottle - an electric spring switch activated by pulling on a cord
Rail - steel tracks used for the motor and ore cars
Raise - an opening driven up through the rock
Refuge Area - an area containing air, water and stopping material where miners can barricade themselves in case of an emergency
Rib - the walls of a drift or crosscut
Rock Bolts - bolts that expand into a metal shell and lodge into the rock face for ground support
Round - a series of typically 10 holes drilled for blasting an area
Sand Line - a pipe that carries a sand slurry to backfill mined areas of a stope
Scab - a piece of short timber nailed to other timber for brace supports
Scaling Bar - a bar used to remove loose rock from a face, back or rib
Scam - when geologists, miners and investment companies (usually located in Reno, Vancouver, Toronto for example) bilk the public knowing that what they are selling is not worth the money they have collected from investors
Scoopies - same as LHD
Scrubber - a device used to clean the exhaust from a diesel engine on a motor
Service Raise - an opening that is used for the passage of men or materials from one level to another
Shaft - a vertical or inclined access way into a mine
Shot - any explosive charge that is being or has been detonated
Shot Box - the box that hold the detonator
Shunts - a method of neutralizing blasting circuits
Skip - a bucket used to haul muck up a shaft
Slusher - a winch-like device used for moving muck without a mucker
Slusher Block - a sheave block used to pass the slusher cable through
Slusher Bucket - a scraper pulled by the slusher to move muck
Slusher Pin - an eye bolt anchor used to fasten a sheave block to the ground
Spikes - large nails or square nails with large heads to secure railroad track
Spitter Cord - same as an ignitor cord
Spitting - the act of lighting a fuse
Station - the area or room at each level where the shaft passes through
Steel - rods used to drill holes into the rock
Stench Gas - a harmless, colorless gas with a garlic odor used in emergency evacuation systems
Stop Block - a block placed on the rail that will prevent equipment from rolling along the track
Stope - an area of varying lengths and widths in which ore is mined upward
Stoper - an air driven rock drill used to drill holes upward
Stull - a single piece of timber used to prop up a slab of rock or loose ground
Sump - an area where water is allowed to collect for pumping
Switch - another name for the device that switches two pieces of railroad track
Timber Skip or Raise Skip - a conveyance used to carry supplies or timber up a raise timber slide
Tramp Miner - a miner that goes from job to job - no steady employerZ‰
Track Jack - a jack used to lift railroad tracks and ties or to rerail derailed motors or ore cars
Trip Lights - a flashing light on the end of a train
Tugger - a small electric or air driven hoist
Trunk Line - the main blasting line from a shot box to the work area
Vent Fans - auxiliary fans that direct the ventilation thru the mine
Vent Line - large pipes or fabric tubing that carry ventilation air
Water Line - a pipe carrying water into or out of the mine
Wedges - tapered pieces of woodused to tighten timber blockings
Whip Check - a safety rope or device used on air hose connections
Whiz Bang - a piece of pipe with small holes drilled into it to blow compressed air
Winze - a secondary vertical or inclined shaft
Adit - A tunnel driven horizontally into a mountainside providing access to a mineral deposit.
Agglomeration - Process whereby the mined ore is mixed with cement or lime prior to loading on the leach pad to group fine particles to large pieces.
Anomaly - A statistical abnormality discovered by surveying and plotting geochemical or geophysical patterns over an area of ground. An anomaly suggests the possibility of a mineral deposit.
Assay - The term given to the chemical analysis of rock samples and metals.
Autoclave System - Oxidation process in which high temperatures and pressures are applied to convert refractory sulphide mineralization into amenable oxide ore.
Backfilling - Waste material used to fill the void created by mining an ore body.
Ball Mill - A steel cylinder loaded with steel balls into which crushed ore is fed. The ball mill is rotated,causing the balls to cascade and grind the ore.
Bench - Successive steps/horizontal increments mined as an open pit progresses deeper.
Byproduct - A secondary metal or mineral product recovered in the milling process.
Carbon-in-leach : A recovery process in which a slurry of gold ore, carbon granules and cyanide are mixed together. The cyanide dissolves the gold content and the gold is adsorbed on the carbon: the carbon is subsequently separated from the slurry for further gold removal.
Carbon-in-pulp : Similar to carbon-in-leach process, but initially the slurry is subjected to cyanide leaching in separate tanks followed by carbon-in-pulp. Carbon-in-leach is a simultaneous process.
Collar - The term applied to the timbering or concrete around the mouth of a shaft.
Contained ounces - Represents ounces in the ground without the reduction of ounces not recovered by the applicable metallurgical process.
Concentrate - A powdery product containing the valuable ore mineral from which most of the waste material has been eliminated.
Concentrator - A particular type of milling plant that produces a concentrate of the valuable minerals or metals. The concentrate must then be treated in some other type of plant, such as a smelter,to effect recovery of the metal.
Crushing and Grinding - The process by which ore is broken into small pieces to prepare it for further processing.
Cut-and-fill : A method of stoping in which ore is removed in slices, or lifts and then the excavation is filled with rock or other waste material (backfill), before the subsequent slice is extracted.
Cyanidation - A method of extracting gold or silver from ore by dissolving it in a weak solution of sodium cyanide.
Development - Underground work carried out for the purpose of opening up a mineral deposit. Includes shaft sinking, crosscutting, drifting and raising.
Dilution - The effect of waste or low grade ore being included unavoidably in the mined ore, lowering the recovered grade.
Disseminated Ore - Ore carrying small particles of valuable minerals, spread more or less uniformly through the gangue matter; distinct from massive ore, wherein the valuable minerals occur in almost solid form with very little waste mineral included.
DorČ - Unrefined gold and silver bullion bars usually consisting of approximately 90 percent precious metals which will be further refined to almost pure metal.
Drift - Horizontal underground tunnel driven alongside or through an ore deposit, from either an adit or shaft, to gain access to the deposit.
Blasthole - Drilling holes into rock to place an explosive charge that breaks up the rock.
Diamond - Drilling with a hollow bit with a diamond cutting rim to produce a cylindrical core that is used for geological study and assays. Used in mine exploration.
Infill - Diamond drilling at shorter intervals between existing holes, used to provide greater geological detail and to help establish reserve estimates.
Reverse Circulation - Drilling that produces rock chips rather than core. Faster and cheaper than diamond drilling, the chips are forced by air to surface for examination.
Exploration - Prospecting, sampling, mapping, diamond drilling and other work involved in searching for ore.
Flotation - A process by which some mineral particles are induced to become attached to bubbles and float, and other particles to sink, so that the valuable minerals are concentrated and separated from the worthless gangue.
Foot Wall - The wall or the rock on the underside of a vein or ore deposit.
Grade - The amount of valuable mineral in each ton of ore, expressed as troy ounces per ton or grams per tonne for precious metals and as a percentage for other metals.
Cut-off Grade : The minimum metal grade at which an ore body can be economically mined.
Mill Head Grade - Metal content of mined ore going into a mill for processing. Usually lower than reserve grade because of dilution.
Recovered Grade - Actual metal content of ore determined after processing.
Reserve Grade - Estimated metal content of an ore body, based on reserve calculations.
Hanging Wall - The wall or the rock on the upper side of a vein or ore deposit.
Heap/dump Leaching - A process whereby gold is extracted by "heaping" broken ore on sloping impermeable pads and repeatedly spraying the heaps with a recirculating, weak cyanide solution which dissolves the gold content. The gold-laden solution is collected for gold recovery.
Heap Leach Pad - A large impermeable foundation or pad used as a base for ore during heap leaching.
Hoist - The machine used for raising and lowering the cage or other conveyance in a shaft.
Host Rock - The rock surrounding an ore deposit.
Hydrographic Basins - One of the 260 Hydrographic Areas recognized within the Great Basin by the United States Geological Survey. These areas are used for management of water resources. The hydrographic areas are defined by watershed boundaries that generally correspond to geographic features.
Layback - The amount of material which must be mined for the slope of a pit wall to be at a safe angle.
Long-hole Open Stope - A method of mining involving the drilling of holes up to 90 feet long into an ore body and then blasting a slice of rock which falls into an open space. The broken rock is extracted and the resulting open chamber is not filled with supporting material.
Metallurgy - A term of wide meaning, embracing the practice and science of extracting metals from their ores and the refining of crude metal.
Mill - A plant where ore is ground fine and undergoes physical or chemical treatment to extract the valuable metals.
Milling Circuit - The combination of various processes and systems which concentrate the valuable minerals.
Mineralization - Rock containing an undetermined amount of minerals or metals.
Mining Claim - That portion of public mineral lands which a party has staked or marked out in accordance with federal, provincial or state mining laws to acquire the right to explore for and exploit the minerals under the surface.
Open Pit - A mine that is entirely on the surface.
Ore - Rock, generally containing metallic or non-metallic minerals, that can be mined and processed at a profit.
Ore Body - A sufficiently large amount of ore that can be mined economically.
Oxide Ore - Mineralized rock in which some of the original minerals have been oxidized. Oxidation tends to make the ore more porous and permits a more complete permeation of cyanide solutions so that minute particles of gold in the interior of the minerals will be readily dissolved.
Patenting - A process established under the General Mining Law of 1872 which permits the conversion of mining claims on federal lands into full fee ownership, provided certain conditions are met.
Pregnant Pond - Pond containing solution which has percolated through the ore on a heap leach. The solution is impregnated with gold and silver removed from the ore.
Raise - A vertical hole between mine levels used to move ore or waste rock or to provide ventilation.
Ramp - An inclined underground tunnel which provides access for exploration or a connection between levels of a mine.
Reclamation - The process by which lands disturbed as a result of mining activity are reclaimed back to a beneficial land use. Reclamation activity includes the removal of buildings, equipment,machinery and other physical remnants of mining, closure of tailings impoundments, leach pads and other mine features, and contouring, covering and revegetation of waste rock piles and other disturbed areas.
Recovery Rate - A term used in process metallurgy to indicate the proportion of valuable material obtained in the processing of an ore. It is generally stated as a percentage of the material recovered compared to the total material present.
Refining - The final stage of metal production in which impurities are removed from the molten metal.
Refractory Material - Gold mineralized material in which the gold is not amenable to recovery by conventional cyanide methods without any pretreatment. The refractory nature can be either silica or sulphide encapsulation of the gold or the presence of naturally occurring carbons which reduce gold recovery.
Reserves - That part of a mineral deposit which could be economically and legally extracted or producedat the time of the reserve determination. Reserves are customarily stated in terms of ore when dealing with metalliferous minerals.
Proven Ore - Material for which tonnage and grade are computed from dimensions revealed in outcrops,trenches, underground workings or drill holes; grade is computed from the results of adequate sampling; and the sites for inspection, sampling and measurement are so spaced and the geological character so well-defined that size, shape and mineral content are established.
Probable Ore - Material for which tonnage and grade are computed partly from specific measurements,samples or production data and partly from projection for a reasonable distance on geological evidence: and for which the sites available for inspection, measurement and sampling are too widely or otherwise inappropriately spaced to outline the material completely or to establish its grade throughout.
Resource/mineralized Material - Mineralization based on geological evidence and assumed continuity. May or may not be supported by samples but is supported by geological, geochemical, geophysical or other data.
Roasting - The treatment of ore by heat and air, or oxygen enriched air, in order to remove sulphur,carbon, antimony and arsenic.
Semi-autogenous Grinding (SAG) - A method of grinding rock into fine powder whereby the grinding media consist of larger chunks of rocks and steel balls.
Shaft - A vertical passageway to an underground mine for moving personnel, equipment, supplies and material including ore and waste rock.
Slurry - A mixture of crushed and finely ground solids with water.
Smelting - A metallurgical operation in which metal is separated from impurities by a process that includes fusion.
Stope - An area in an underground mine where ore is mined.
Strike Length - The longest horizontal dimension of an ore body or zone of mineralization.
Stripping Ratio - The ratio of the number of tons of waste material removed to the number of tons of ore removed, used in connection with open pit mining.
Sulphide Ore - A sub-group of refractory ore - mineralized rock in which much of the gold is encapsulated in sulphides and is not readily amenable to dissolution by cyanide solutions - associated with sulphide minerals (primarily pyrite) that have not been oxidized. Some sulphide ore may require autoclaving or roasting prior to cyanidation.
Tailings - The material that remains after all metals considered economic have been removed from ore during milling.
Tailings Dam - A natural or man-made area suitable for depositing the material that remains after the treatment of ore.
Trenching - An exploration technique in which trenches are dug to expose potential ore for geological examination or assays.
Troy Ounce - Troy ounce of a fineness of 999.9 parts per 1,000 parts, equal to 31.1034 grams.
Water Management - The process whereby the groundwater table in the mining area is lowered by pumping water from wells, and the water is conveyed and used or recharged to the groundwater system through infiltration, reinjection or irrigation return.


If you have any terms which are not listed here please forward them
to me for inclusion in the list. These are all terms familiar to geologists,
professional miners, tramp miners and others associated with mining.

Copyright'96/'97/'98/'99/'00Last updated 9/30/00


If you think this site is terrific please click the link below to vote for this as one of your favorite rockhounding sites.


To contact us by email please click here.