ADIT: A nearly horizontal passage driven from the surface to the mine workings.

AERIAL SURVEY: A survey made from an aircraft, such as photographic, magnetometer, radio-activity, etc.

ALLUVIAL DEPOSIT: Clay, sand, gravel, etc, removed from a parent rock by the action of water and weathering agents and deposited at a distance

ALTERATION: Any physical or chemical change in a rock or mineral subsequent to its formation.

AMALGAMATION: A process by which gold and silver are extracted from an ore by dissolving them in mercury.

ANOMALY: A term used in geophysics to describe any change in subsidence conditions as detected by geophysical instruments. In other words, it is any change from the normal and may be caused by such factors as mineralisation, change in rock types, structural conditions or even depths of overburden. An anomaly suggests the possibility of a mineral deposit, but only one of thousands of anomalies ever leads to a worthwhile mineral discovery.

ANTICLINE: An arch or fold in the layers of rock shaped like the crest of a wave, as opposed to a syncline which is similar to the trough of a wave.

ASSAY: The testing of a sample of minerals or ore to determine the content of valuable minerals in the sample.

AUTHORITY TO PROSPECT (AP): See Tenements. BACK: The ceiling or roof of any underground excavation.

BACKFILL: Waste material used to support the walls of a stope and provide a working platform after removal of the ore.

BALL MILL: A piece of milling equipment used to grind ore into small particles. It is a cylindrical shaped steel container filled with steel balls into which crushed ore is fed. The ball mill is rotated, causing the balls themselves to rotate, which in turn grind the ore.

BASE METAL: A commercial metal such as copper, lead or zinc. The term was coined to describe a metal 'inferior' to precious metals such as gold and silver.

BEDROCK: The solid rock forming the earth's crust, frequently covered by over-burden or water.

BENEFICIATE: To concentrate or enrich. The term is generally applied to the preparation of iron ore for smelting, through such processes as sintering, magnetic concentration, washing, etc.

BENCHING: A system of working in stages or steps in an open-cut

BIOLOGICAL LEACHING: A process for recovering metals from low-grade ores by dissolving them in solution, the dissolution being aided by bacterial action.

BIT: The cutting end of a boring instrument in rock drilling, it is frequently made with ultra-hard material such as diamonds or tungsten carbide.

BLISTER: Unrefined copper produced from smelting copper ores.

BLOCK CAVING: A low cost method of mining in which large blocks of ore are undercut, causing the ore left in place to break and cave under its own weight. BORD: An underground passageway made in solid coal.

BY-PRODUCT: A secondary or additional mineral or mineral product.

BOX HOLE: A short raise or opening drive above a drift for the purpose of drawing ore from a stope, or to permit access.

BREAST: A working face, usually restricted to a stope.

BULLION: Gold or precious metal in bars or similar form, prior to being formed into other shapes such as coins. Also applied to silver- bearing lead from a blast furnace.

CAGE: The conveyance used to transport men and equipment in a shaft.

CAP: The outcrop of a lode.

CARBON-IN-PULP (CIP): A metallurgical process for extracting gold from a cyanided slurry in which the gold is absorbed onto the surface of activated carbon.

CHUTE: A channel cut in rock or constructed of timber through which ore is passed from a higher to a lower level.

CLAIM: An area of land or water 'claimed' by a prospector or mining organisation for the purpose of exploring the claim for a certain length of time and subject to certain conditions. Claims are first staked out and then recorded in the appropriate state Department of Mines. The common size is 16.2 ha.

CLEAN UP: To collect periodically all the valuable product from an operation in a stamp mill, sluice box, etc.

COMPLEX ORE: An ore containing a number of minerals of economic value usually implying difficult metallurgy to extract them.

CONCENTRATE: A product containing the valuable metal and from which most of the waste material in the ore has been eliminated.

CONGLOMERATE: A sedimentary rock consisting of rounded, water-worn pebbles or boulders cemented together into a solid mass.

CONTAMINATION: Waste or ore material which dilutes a sample and derives from outside the volume which that sample is deemed to represent.

CORE: The long cylinder or rock, about one inch in diameter, that is recovered by the diamond drill.

COSTEAN: A trench cut across the line of a lode.

COUNTRY ROCK: A loose term to describe the general mass of rock adjacent to an orebody, as distinguished from the vein or ore deposit itself.

CROSSCUT: A horizontal opening driven across the course of a vein or structure, or in general across the strike of the rock formations. A connection from a shaft to an ore structure.

CRUSHER: A machine for crushing rock, such as a gyratory crusher, jaw crusher, stamp mill, etc.

CUT AND FILL: A stoping method in which the ore is removed in slices or 'lifts', after which the excavation is filled with rock (backfill) or other waste material before the next slice is mined. The backfill supports the walls of the slope as well as acting as the working floor for the next stage of mining.

CUT-OFF BOUNDARY: A geologically interpreted boundary enclosing areas of rock which are deemed to have a grade which does not fall below a specified cut-off grade.

CYANIDATION: A method of extracting gold or silver by dissolving it in a weak solution of sodium cyanide.

DEPLETION: The steadily declining amount of ore in a deposit or property resulting from production. Minerals are said to be a 'depleting resource' because once mined, they cannot be replaced.

DEVELOPMENT: Bringing a mining property to the production stage. Technically, the carrying out of works to gain access to the orebody.

DIAMOND DRILL: A rotary type of rock drill in which the cutting is done by abrasion rather than percussion. The cutting bit is set with diamonds and is attached to the end of long hollow rods through which water is pumped to the cutting face. The drill cuts a 'core' of rock which is recovered in long cylindrical sections, about 2.54cm in diameter.

DIFFERENTIAL FLOTATION: A milling process using the flotation process, by which concentrates are made of each of the various valuable minerals in an ore.

DILUTION: A lowering of the grade of ore being mined when waste rock or low-grade ore are included unavoidably in the mined ore.

DIP: The angle at which a vein, structure or rock bed is inclined from the horizontal, measured at right angles to the strike.

DISSEMINATED ORE: Ore carrying small particles of valuable minerals, spread through the gangue matter. Opposed to massive ore, wherein the valuable minerals occur in almost solid form with very little waste material included.

DREDGING: Raising silt, loose sand, etc, in a scoop or by suction. Used for such minerals as alluvial gold and tin.

DRIFT: A passage driven through country rock to intersect a seam or vein.

DRIVE: A level along the course of a lode or reef.

ELECTROLYTIC: Pertaining to a refining process in which impure metal from a smelter is suspended in a cell containing a liquid known as electrolyte. The metal to be refined forms the positive post or 'anode' and is deposited out on the negative post, called the 'cathode', by the electric current fed into the anode.

ELECTROMAGNETIC (EM): The most important of the modern mineral- hunting techniques, most EM equipment imposes or introduces electrical currents from above ground (on the surface or from the air) into the earth, and this electrical activity is measured during and after the currents have passed through rocks or mineral deposits. (See Anomaly).

EXPLORATION LICENCE (EL): See Tenements.

FACE: As applied to a drift, crosscut or stope, is the end in which work is progressing.

FAULT: A break in the earth's crust caused by forces which have moved the rock on one side. This can vary from several km to a few cm in length. Similarly the movement or displacement along the fault may vary widely. Ore deposits are commonly associated with faults, as the movement frequently provides a channel for the passage of ore-bearing solutions.

FERROUS: Mineral that contains iron: 'non-ferrous' is a standard term for other minerals.

FIRE ASSAY: Any assay procedure involving heating the sample in a furnace to ensure complete extraction of all the contained precious metal.

FINES: Literally, very fine iron ore resulting from the crushing of the rough raw material. Fines are too small to use in a blast furnace and must be consolidated to do so.

FLOTATION: A milling process by which some mineral particles are induced to float and other to sink. In this way the valuable minerals are concentrated and separated from the worthless gangue.

FLUX: A salt or other mineral added in smelting to assist fusion. FOLD: Any bending or wrinkling of a rock strata.

FOOTWALL: The wall or rock on the underside of a vein or ore structure.

GANGUE: The worthless minerals associated with valuable minerals in an ore deposit.

GEIGER COUNTER: A device that gives an indication of the presence of radio-active minerals.

GEOPHYSICS: A scientific method of prospecting that utilises the physical properties of minerals to detect their presence. Common properties include magnetism, specific gravity, electrical conductivity and radio-activity.

GLORY HOLE: An open-cut or pit mine in the earth's surface to reach and mine out an ore deposit with extraction from the bottom level via an adit or underground markings.

GOSSAN: An iron oxide deposit resulting from the oxidation and leaching of a sulphide mineral body containing such minerals as pyrite.

GRAB SAMPLE: A sample taken at random to determine if valuable elements are contained in the rock.

GRADE: (To contain a particular) quantity of ore or metal relative to other constituents.

GRAVITY METER (GRAVIMETER): An instrument that measures the gravitational attraction of the earth. This varies with the density of rocks being probed. The results of a gravity survey may indicate favorable areas to be further explored.

GRIZZLY: A grating placed over the top of a chute or ore pass to stop the larger pieces of rock or ore which would otherwise block the chute or damage the waiting conveyance.

GROSS VALUE: The theoretical value of ore in the ground, determined simply by applying the assay of metal or metals and the current market price.

GRUBSTAKE: Money and/or supplies given to a prospector on the understanding that the supplier or financing party will share in any discovery the prospector may make.

HANGING WALL: The wall or rock on the upper or top side of a vein or ore deposit.

HEADGRADE: The average grade ore fed into a mill.

HOIST: A machine which raises and lowers the cage and skips in a mine shaft.

HYDRO-METALLURGY: Separation of the metal in aqueous solution from the rest of the ore, followed by precipitation in metallic form.

IGNEOUS ROCKS: Rocks formed by the solidification of molten material that originated within the earth.

INDUSTRIAL MINERALS: Usually non-metallic minerals which are used in industry and manufacturing processes in their natural state, though generally with some beneficiation to imposed specifications; examples include asbestos, salt, gravels, building materials, tale and sands.

JAW CRUSHER: Machine in which the rock is broken by the action of moving steel jaws. JIG: An apparatus used in milling to concentrate ore on a screen submerged in water, either by a reciprocating motion of the screen or by the pulsation of water through it.

LAGGING: Planks or timbers usually placed under the roof of a stope or drive to prevent rock from failing.

LANDSAT: An unmanned satellite designed to provide multispectral imagery of the Earth's surface.

LEAD: Placer gravels on the surface.

LEACHING: A chemical process used in milling for the extraction of valuable minerals from ore. Also, the natural process by which ground waters dissolve minerals, thus leaving the rock with a smaller proportion of someof the minerals than it contained originally.

LENS: An orebody in the form of a convex lens.

LEVEL: The horizontal passages on a working horizon in a mine, it is customary to work mines from a shaft, establishing levels at regular intervals, generally 30.5 m to 45.6 m apart. They are numbered in sequence below surface, or named by the depth at which they lie below surface.

LODE: A mineral deposit in solid rock.

LUMPS: Chunks of consolidated iron ore that result from the crushing of the rough raw material.

MAGNETOMETER: A device to measure the magnetic attraction of rocks beneath the surface. By surveying a territory with a magnetomoter (in air- borne exploration, it is trailed beneath the aircraft), the character of the magnetic field of the area below can be plotted and anomalies indicated.

MARGINAL ORE DEPOSITS: Lower grade orebodies which are close to being uneconomic to mine.

MATRIX: Rock containing a mineral or metallic ore as well as waste material.

MATTE: The product or a smelter, being metal with some contained sulphur. It must be further refined to obtain the pure metal.

METAMORPHIC ROCKS: Rocks that have undergone a change in texture or composition subsequent to their first solidification, through such factors as heat, pressure, etc.

METALLURGIC RECOVERY: The quantity of mineral metal or other desired material which is finally produced by a treatment plant as a proportion of the estimated quantity of the same mineral in the ore being fed into the plant.

METALLURGY: The science of preparing metals for use by separating them from their ores.

MILL: A plant in which ore is ground and treated for the recovery of the valuable metals contained.

MINERAL: A substance which may or may not be of economic value, that occurs naturally in the earth. It is homogeneous, has a certain chemical makeup and usually appears in crystal or grain form.

MINING DILUTION: The contamination of defined ore with designated waste material during the course of mining. Expressed as a percentage of the ore tonnage.

MINING RECOVERY: The percentage of defined ore tonnage which is actually delivered to the treatment plant or ore stockpile.

MUCK: Development ore or rock that has been broken by blasting.

MUCKING MACHINE: A machine for moving or loading ore or waste which is generally driven by compressed air and used in a tunnel or shaft.

MULLOCK: The accumulated waste or refuse rock about a mine.

NECK: A lava-filled conduit of an extinct volcano exposed by erosion.

NUGGET: A water-worn piece of native gold of some size.

OPEN-CUT OR OPEN PIT: A surface working, open to daylight.

OPTION: A right to have the first chance to buy or refuse to buy a property or an asset of some kind. In mining, it often refers to a contract that covers a mining claim or groups of claims.

ORE: A rock from which economic minerals may be obtained profitably.

OREBODY: A solid and fairly continuous mass of ore which may include low grade and waste as well as pay ore but is separate in form and character from the country rock.

ORE DRESSING: The treatment process in a mill. (See Mill).

ORE RESERVE: The tonnage of ore actually available for extraction, or in stock.

OUTCROP: An exposure of rock or a mineral deposit that can be seen on the surface, ie, it is not covered by overburden or water.

OVERBURDEN: Worthless unconsolidated surface material, such as earth, sand and boulders, covering the rock surface.

PASS: An opening in a mine through which ore is delivered from a higher to a lower level. PEG: To mark out a claim or lease.

PELLETS: Small balls of treated iron ore, prepared for shipment to steel companies as raw material in the steel-making process.

PIG IRON: The crude cast iron from a blast furnace.

PINCH: The narrowing of a vein or a deposit.

PILOT PLANT: Equipment set up on a small scale to duplicate a practical production plant; its purpose is to test a process prior to the commitment to build a full-scale plant.

PIPE: A cylindrical siliceous intrusion formed as an offshoot from a larger igneous intrusion often containing such minerals as tin, copper, molybdenum, bismuth, tungsten, gold, etc.

PITCH: The dip or inclination of a vein or bed or the inclination of an ore body in the direction of its strike.

PLACER: A sand and gravel deposit which contains a valuable mineral such a gold, platinum, tin, rutile or diamonds.

PLAT: The floor of a level near its intersection with a shaft.

POCKET: A small body of ore; an enlargement of a lode or vein; an irregular cavity containing ore.

PRECIOUS METALS: Metals such as gold and silver which are valued for other than ordinary industrial uses. (See Base Metals).

PRIMARY MINERALS: Those minerals that retain their original form and composition, as original sulphides.

PROBABLE ORE RESERVES: Extensions near at hand to proved ore where the conditions are such that ore will probably be found but where the extent and limiting conditions cannot be so precisely defined as for proved ore. Probable ore may also include ore that has been cut by drill holes too widely spaced to assure continuity.

PROSPECT: A mining property, the value of which has not been proved by exploration.

PROVED ORE RESERVES: Ore which has been blocked out in three dimensions by drilling, but including in addition, minor extensions beyond actual drill holes, where the geological factors that limit the ore body are definitely known and where the chance of failure of the ore to reach these limits is so remote as not to be a factor in the practical planning of mine operations.

RAISE: A vertical or inclined underground tunnel that has been excavated from the bottom upward.

RECOVERY: The amount of mineral that is separated and recovered in a mill, expressed as a percentage of that calculated to be in the original ore.

REFINING: The final purification process of a metal or mineral. (See Electrolytic).

RESERVES: Ore reserves fall into four general categories-proven, probable, possible and indicated. Proven is ore that has been blocked out on four sides; probable is ore that has been opened on two or three sides, while possible ore has been opened on one side only; indicated ore is ore that has been outlined by diamond drilling but which has not been opened by underground work.

ROASTING: The treatment of ore by heat in order to remove sulphur and arsenic.

ROCK: Any naturally formed combination of minerals constituting an appreciable part of the earth's crust.

ROCK BOLTING: The act of consolidating roof strata by means of anchoring and tensioning steel bolts and dowels in holes drilled for the purpose.

ROCK BURST: The sudden failure of walls or pillars in a mine caused by the weight or pressure of the surrounding rocks.

ROCK MECHANICS: A study of stress conditions surrounding mine openings and the ability of rocks, and underground structures, to withstand such stresses.

ROD MILL: A rotating cylindrical mill which employs steel rods as a medium for grinding ore into small pieces.

ROTARY AIR BLAST DRILLING: A drilling process using a rotating drill bit to cut the rock and compressed air to recover the cuttings.

ROYALTY: Amounts of money paid by a company operating a mining property to the actual owner of the mineral rights to the property. The royalty may be based on so much per tonne produced or by a percentage of revenue or profits.

RUN-OF-MINE: Ore of average grade in a mine.

SCALING BAR: A bar-like instrument for wedging 'loose' (material) from the walls or back of a working place.

SCINTILLOMETER: An instrument for detecting and measuring, radioactivity in minerals or rock. It is sensitive to gamma rays emitted by radioactive minerals such as uranium more sensitive than the Geiger counter.

SECONDARY ENRICHMENT: An enrichment of a vein or orebody by minerals which have been taken into solution from one part of the vein or adjacent rocks and re-deposited in another.

SEDIMENTARY ROCKS: Secondary rocks formed from rock particles which are laid down under water, eg, limestone, shale, sandstone. A characteristic feature of sedimentary deposits is a layered structure known as bedding or stratification.

SEISMIC PROSPECTING: A geophysical method of prospecting, utilising the knowledge of the speed and reflection of sound waves in rock.

SHAFT: A vertical or inclined excavation for the purpose of opening and servicing a mine. It is usually equipped with a hoist at the top, which lowers and raises a conveyance for handling men and materials.

SHEAR OR SHEARING: The deformation of rocks by lateral movement along innumerable parallel planes providing a favorable location for the deposition of ore.

SHOOT: A concentration of mineral values. That part of a vein or zone carrying values or ore grade.

SHRINKAGE STOPE: A method of stoping which utlises part of the broken ore as a working platform and as support for the walls.

SILL: An intrusive sheet of igneious rock of approximately uniform thickness and generally extending over a considerable lateral extent. It has been forced between level or gently inclined beds.

SILL FLOOR: The first cut in a stope.

SKIP: A self-dumping type of bucket used in a shaft for hoisting ore or rock .

SLASH: Rock blasted from the wall back or floor of a working place.

SLUICING: Washing earth through long races or boxes provided with riffles. Used mainly for heavy minerals such as gold and tin.

SLUSHER: A mechanical drag shovel used to move ore or waste in a stope or tunnel.

SMELTING: The partial recovery of metal from processed ore. The latter will have been treated and concentrated at a mill, but smelting is required to actually recover the metal content and convert it to a form that is ready for refining.

SQUARE SET: A set of timbers used for support in underground mining.

STAKING: The measuring of an area and marking with stakes or posts to establish mineral rights.

STATION: An enlargement of a shaft made at the level horizon used primarily for the storage and handling of equipment.

STOCK PILE: Broken ore accumulated in a heap on surface, pending treatment or shipment.

STOPE: An excavation in a mine from which ore is being or has been extracted.

STRATUM: A bed or layer of sediment.

STRIKE: Trend or direction of rock strata in a horizontal place; to extend in that particular direction.

STRIKE LENGTH: The long dimension of a geological feature such as a bed, vein or fault where it intersects a horizontal plane, esp. ground surface.

STRIP: To remove an overburden covering an orebody.

SULPHIDE ZONE: That part of a mineralised deposit in which the original minerals (often sulphides) have not been altered. Found below the oxidised zone. SUMP: An excavation for the purpose of catching or storing water. The bottom of a shaft is commonly used for this purpose.

SYNCLINE: A down-arched fold in bedded or stratified rocks.

TAILINGS: Material rejected from a mill after the recoverable valuable minerals have been extracted.

TEMPORARY RESERVE: See Tenements.

TENEMENTS: The general term used to describe large tracts of land granted to mining companies and prospectors by Australian State Governments for general 'grass roots' exploration. But the name and relevant conditions varies from State to State as each has its own Mining Act. The relevant details are as follows.
New South Wales- A Tenement is known as an Exploration Licence (EL) and can be no larger than 256 sq. km. It is necessary to spend about $25,000 a year for two years on exploration and it is valid for two years with a finite term (on re-application) of five years. If the mining company holding a tenemant believes it to be a potential mining lease, it then applies for a Prospecting Licence.
Northern Territory- A Tenement is known as an Exploration Licence (EL) and can be no larger than 1,280 sq. km, with no one company holding more than 12,800 sq. km in total. It is necessary to spend about $25,000 a year for two years on exploration, and it terminates after 12 months with a finite life of five years if re-application is desired. If the mining company holding a tenement believes it to be a potential mining lease, it then applies for a Prospecting Licence.
Queensland- A Tenement is known as an Authority to Prospect (A to P) and the relevant company must spend $20,000 on exploring the tenement in the first year and a further $30,000 in the second year. It is granted for a term of two years, but re-application for a longer term can be made.
South Australia- A Tenement is known as an Exploration Licence (EL) and there appears to be no limit on the area that can be held. It is necessary to spend about $25,000 a year for two years and it has a maximum life of two years. If the mining company holding a tenement believes it to be a potential mining lease, it then applies for a Mineral Claim.
Tasmania- A Tenement is known as an Exploration Licence (EL) and all conditions are subject to the discretionary powers of the Minister for Mines. To retain an EL, the relevant company must spend around $25,000 a year for two years, on exploration, and the EL expires after six months with the holder having the right to re-apply for an extension.
Victoria- A Tenement is known as an Exploration Licence and there are no specific requirements in regard to size. It is usual to require an Exploration Company to spend approx. $25,000 a year for two years, but the Act is under considerable review as at this time.
Western Australia- A Tenement is known as a Temporary Reserve (TR) and can be a maximum 200 km in size, with the holder spending $20,000 a year to retain it. Each TR has a life of 12 months but can be held almost indefinitely if the company continues to re-apply for an extension and pay the required annual fee. If the Mining Company believes it to be a potential mining lease, it then applies for a mineral claim.
Many of these rules are designed to prevent Companies holding large tracts of land for long periods with no direct action, and more complete details must be obtained from the relevant State Authorities.

TUNNEL: Strictly a passage open at both ends. Often this term is loosely used for adit, drift or drive.

VEIN: An opening, fissure or crack in rock containing mineralised material.

WALL ROCK: The rock forming the walls of an underground opening.

WASH: An loose surface deposits of sand, gravel, boulders, etc.

WASTE: Material that is too low in grade to be of economic value.

WINZE: An underground opening similar to a shaft but not starting at the surface.

ZONE: An area or region which is distinct from the surrounding rock either because of a difference in the type of structure of rocks, or because of mineralisation.