Mining Play of 2007

Mining Glossary

Apr 27th, 2007 by admin

Term	Definition
Acid Rock Drainage (ARD)	Acid Rock Drainage (ARD) is a natural weathering process where sulphide minerals exposed to water and air react to produce acid.Â ARD occurs where large quantities of sulphur-containing rock minerals are produced, and can be observed in road and airport construction and at mines(mine rock piles, tailings, rock walls in open pits).Â Resultant acidic water dissolves other minerals, potentially increasing the metal content in the water to levels that are deleterious to aquatic habitat.Â
Activated carbon	Activated carbon has the ability to capture and extract gold from a gold solution. Small granules of carbon between 1/16 and 1/8 of an inch across are normally made from coconut shells for use in metallurgical plants. After heating to red heat in an oxygen-free atmosphere, the carbon is activated, and among other characteristics it attracts and binds with gold, releasing it from a cyanide solution.
Adit	A tunnel driven horizontally into a mountainside, providing bottom access to a mineral deposit and/or helping to drain water.
Alteration	Any physical or chemical change in a rock or mineral subsequent to its formation. Milder and more localized than metamorphism.
Anomaly	An anomaly is a departure from the norm which may indicate the presence of mineralization in the underlying bedrock. Geochemical anomalies and Induced Polarization (IP) anomalies are two of the most common anomalies described in exploration. “Anomalies” are easily found or generated, and investing on the basis of such an anomaly is highly speculative. If a geophysical and geochemical anomaly coincide, the probabilities are improved, but even if mineralization is discovered this in no way guarantees it will be economic.
Anticline	An arch or fold in layers of rock shaped like the crest of a wave.
Assay	The chemical analysis of an ore, mineral, concentrate of metal to-determine the amount of valuable metals contained. Precious metals are usually given in ounces per short ton or grams per metric tonne, while base metals are given in percentage.
Autoclave System	Oxidation process in which high temperatures and pressures are applied to convert refractory sulphide mineralization into more amenable oxide ore. NB this is a particularly good system if the ore contains arsenic, since it traps this element in an environmentally benign compound. Autoclaves are not normally good if the ore contains carbon or carbonates.
Backfilling	Waste material used to fill the void created by mining an ore body. This can simply be broken rock from tunnelling that is tipped into a stope, or it can be crushed ore from which gold has been extracted that is pumped back underground.
Base Metal	Any non-precious metal (e.g. copper, lead, zinc, nickel, etc.).
Bench	Successive steps/horizontal increments mined as an open pit progresses deeper.Â Bench heights of 30 feet are typical but can vary to suit required selectivity of mining.
Block Caving	An inexpensive method of mining in which large blocks of ore are undercut, causing the ore to break or cave under its own weight.
Bornite	Bornite is an important copper ore mineral. It ranks up there with many of the other copper ores such as chalcocite, chalcopyrite, covellite, digenite, cuprite and tetrahedrite. Bornite copper content is 50% atomic ratio.
Breccia	A rock in which angular fragments are surrounded by a mass of fine-grained minerals.Â These fragments may be produced by volcanic explosion, faulting or sedimentary deposition.Â The sharpness of the fragments indicates that they did not travel far from where they fractured.Â
Bulk Mining	Any large-scale, mechanized method of mining involving many thousands of tons of ore being brought to surface per day.
bullion	the product of smelting or refining precious metals, usually in the form of bars or ingots
By-product	A secondary metal or mineral product of economic value recovered in the extraction process. Typical gold mine by-products are silver, copper and zinc.
Carbonaceous Ore	Ore containing particles of carbon material can reduce gold recoveries. Natural carbon can compete with the activated carbon introduced in the treatment process for gold which has been liberated by the cyanide leach. Activated carbon introduced in the process has a large grain size and is captured on screens. After the ore is crushed and ground, natural carbon will be much finer and is lost to the tailings together with any gold which has attached to it. Roasting carbonaceous ore is one route to improve recoveries.
Carbon-in-leach (CIL)	A recovery process in which a slurry of gold ore, activated carbon granules and cyanide are mixed together. The cyanide dissolves the gold content and the gold is absorbed on the carbon. The carbon is subsequently separated from the slurry for further gold removal.
Carbon-in-pulp (CIP)	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. This is a better process if there is some carbon in the ore.
Cash Costs	Includes site costs for all mining, processing, administration, resource taxes, and royalties but does not include capital, exploration, depreciation, and financing costs. Total cash costs are reduced using by-product credits, and are then divided by payable gold ounces to arrive at net cash cost of production per ounce. This is a non GAAP measure.
Chalcocite Â	Chalcocite is an important copper mineral ore. It has been mined for centuries and is one of the most profitable copper ores. The reasons for this is its high copper content (67% atomic ratio and nearly 80% by weight) and the ease at which copper can be separated from sulfur.
Chalcopyrite	Chalcopyrite (or copper pyrite), is one of the minerals refered to as “Fool’s Gold” because of its bright golden color. As a copper ore, the yield of chalcopyrite is rather low in terms of atoms per molecule. It is only 25%, compared to other copper minerals such as chalcocite, Cu2S - 67%; cuprite, Cu2O - 67%; covellite, CuS - 50% or bornite Cu5FeS4 - 50%. However the large quantities and widespread distribution of chalcopyrite make it the leading source of copper. Chalcopyrite is a common mineral and is found in almost all sulfide deposits.
Channel SampleÂ	A sample composed of pieces of vein or mineral deposit that have been cut out of a small trench or channel, usually about ten cm wide and two cm deep.Â These are usually the first samples taken from an ore deposit that are of significance.Â Grab samples refer to samples of outcrop that are taken at the early stages of exploration, but they are not as significant as they may represent only a few highly concentrated samples based upon visual indications.Â
Chip SampleÂ	A method of sampling a rock exposure whereby a regular series of small chips of rock is broken off along a line across the face.Â
Chute	An opening, usually constructed of timber and equipped with a gate, through which ore is drawn from a stope into mine cars.
Commercially Mineable Ore Body	A mineral deposit that contains ore reserves that may be mined economically.
Complex Ore	An ore containing a number of minerals of economic value. The term often implies that there are metallurgical difficulties in liberating and separating the valuable metals.
Concentrate	If gold is intimately mixed with, for example, copper sulphides, it may be most economic to create a concentrate containing both metals, for further treatment at a smelter. The concentrate is a powdery product containing the valuable ore mineral from which most of the waste material has been eliminated.
Concentrator/Float plant	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.
Cone Crusher	A machine which crushes ore between a gyrating cone or crushing head and an inverted, truncated cone known as a bowl.
Conglomerate	A sedimentary rock consisting of rounded, water-worn pebble or boulders cemented into a solid mass.
Contact	A geological term used to describe the line or plane along which two different rock formations meet.
Copper Oxide Â	There are two major divisions of copper classes found in copper porphyry deposits.Â These are oxides and sulphides.Â Copper oxide, often referred to as “supergene”, are the more highly concentrated material generally found at the top of a deposit.Â
Copper PorphyriesÂ	Copper porphyries are large low-grade stockwork to disseminated deposits of copper which may also carry minor recoverable amounts of molybdenum, gold and silver. Usually they are copper-molybdenum or copper-gold deposits. They must be amenable to bulk mining methods, that is open pit or, if underground, block caving. Most deposits have copper grades of between 0.4-1%, and are up to several billion tonnes in size. The typical porphyry copper deposit occurs in a cylindrical, stock-like, composite intrusion having an elongate or irregular outcrop about 1.5 x 2 km, often with an outer shell of equigranular medium-grained rock. The central part is porphyrite - implying a period of rapid cooling to produce the finer-grained groundmass - the porphyry part of the intrusion.
Copper Sulphide	Copper sulphide, often referred to as “hypogene”, is the copper mineralization generally found at the bottom of a deposit.
Core	The long cylindrical piece of rock, about an inch in diameter, brought to surface by diamond drilling.
Crosscut	A horizontal opening driven from a shaft and (or near) right angles to the strike of a vein or other orebody.
Crushing and Grinding	Mined ores have to be crushed and milled into a fine powder to liberate the economic mineral particles in a number of stages. The primary crushers are used for the initial phase after the ore is conveyed to stockpiles. Conventional milling circuits takes the coarse ore through secondary, and possibly tertiary, crushing which produces pebble-sized fine ore. The fine ore is then fed into a grinding circuit of rod and ball mills, which reduce the ore to fine powder. Water is added during the milling process.
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.
Cut-off grade	the lowest grade of mineralized material considered economic; used in the calculation of the ore reserves in a given deposit
Cutting assays	In some gold mines very high grades are detected periodically, but if the actual result is included in the grade calculation for large blocks of ore it often overestimates the gold content of the block. Hence it’s common in greenstone mines to “cut” high grade assays back to a standard level to limit the impact of small tonnages of very high grade gold in larger ore blocks.
Cyanidation (cyanide leaching)	A method of extracting gold or silver from ore by dissolving it in a weak solution of sodium cyanide. After the precious metal is dissolved, the ground rock is separated from the solution and then the gold is precipitated from the solution, normally using zinc powder. If there is little silver in solution precious metals can be extracted from the leachate using activated carbon.
Decline	An underground passageway connecting one or more levels in a mine, providing adequate traction for heavy, self-propelled equipment. Such underground openings are often driven in an upward or downward spiral, much the same as a spiral staircase.
Deposit	A mineralized body, which has been physically delineated by sufficient drilling, trenching, and/or underground work, and found to contain a sufficient average grade of metal or metals to warrant further exploration and/or development expenditures. Such a deposit does not qualify as commercially mineable tons or as containing material reserves until final technical and economic factors have been resolved.
Development	Work carried out for the purpose of opening up a mineral deposit and making the actual ore extraction possible.
Development Drilling	Drilling to establish accurate estimates of mineral reserves.
Diamond Drill	A rotary type of rock drill that cuts a core of rock that is recovered in long cylindrical sections, two centimeters or more in diameter.
Dilution	The effect of waste or low grade ore being included unavoidably in the mined ore, lowering the recovered grade. However, it should be checked with the gold producer whether the grade of the quoted reserves is before or after dilution as this can have a significant effect on cash costs.
Dip	The inclination of a planar surface, measured in the vertical plane perpendicular to its strike. A steeply dipping orebody is generally easier to mine than a flatter one since gravity helps move ore.
Direct shipping ore	Sometimes a mine has very high grade ore that requires treatment in a smelter, and the cost of building a treatment plant is unnecessary. In this case this direct shipping ore goes directly to the smelter.
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.
Dore	Impure and unrefined mixture of metallic gold and silver produced through the smelting of gold and silver concentrate, sand or precipitate. Typical impuritics include base metals. DorÃ© is further refined to almost pure gold by a smelter or refinery.
Drift	A horizontal underground opening that follows along the length of a vein or rock formation as opposed to a cross-cut which crosses the rock formation.
Drill Core	The cylindrical piece of rock, usualy between one and three inches in diameter brought to surface by diamond drilling.
Drill-indicated Reserves	The size and quality of a potential orebody as suggested by widely spaced drill holes; more work is required before reserves can be classified as probable or proven.
Due Diligence	The degree of care and caution required before making a decision; loosely, a financial and technical investigation to determine whether an investment is sound.
Electro-winning	Recovery of a metal from solution by means of electrochemical processes. This is often used as a penultimate step in capturing gold from the CIP/CIL process.
Elution	The process used to recover gold from activated carbon. Normally the gold is recovered from loaded activated carbon using a hot concentrated cyanide solution. This generates a concentrated gold solution from which gold can be precipitated using electro-winning. Precipitated gold is melted into dorÃ© bars, and the carbon is re-activated in a furnace and re-cycled.
Enargite	Enargite is a somewhat rare copper mineral. Enargite is related to the rare mineral wurtzite. Wurtzite is a zinc sulfide with a formula of ZnS. In enargite 75% of the zinc atoms are replaced by copper and 25% of the zinc atoms are replaced by arsenic, Cu3AsS4.
Environmental Impact Study	A written report, compiled prior to a production decision, that examines the effects proposed mining activities will have on the natural surroundings.
Epithermal Deposit	A mineral deposit consisting of veins and replacement bodies, usually in volcanic or sedimentary rocks, containing precious metals, or, more rarely, base metals.
Exploration	Work involved in searching for ore, usually by prospecting, geology, geophysics, geochemistry, drilling or driving a drift.
Face	The end of a drift, crosscut or stope in which work is taking place.
Fault	A break in the earth’s crust caused by tectonic forces which have moved the rock to one side with respect to the other. Faults can often be favourable hosts for orebodies or may have channelled ore-bearing fluids to more favourable horizons.
Feasibility Study	A comprehensive study undertaken to determine the economic feasibility of a project; the conclusion will determine if a production decision can be made and is used for financing arrangements
Fissure	An extensive crack, break or fracture in rocks.
Float	Pieces of rock that have been broken off and moved from their original location by natural forces such as frost or glacial action.
Flotation	A process by which mineral particles are induced to become attached to bubbles and float, and other particles to sink, so that the valuable minerals can be collected at the top of the float tanks and separated from waste rock. Flotation is an attractive treatment route since it doesn’t normally attract as much environmental regulation.
Flotation Cells	Flotation cells are commonly used in conventional copper concentrators to separate the copper minerals from the waste rock. After being crushed and ground, the copper ore is pumped into flotation cells. Chemical reagents are added and the mixture is aerated and mechanically agitated. The mineral particles are separated from the host rock and float to the surface on air bubbles, forming a froth, which is skimmed off, filtered and dried.
Footwall	The rock on the underside of a vein or ore structure.
Formation	the ordinary unit of geologic mapping consisting of a large and persistent stratum of rock
Fracture	A break in the rock, the opening of which allows mineral bearing solutions to enter. A “cross-fracture” is a minor break extending at more-or-less right angles to the direction of the principal fractures.
Free Milling	Ores of gold or silver from which the precious metals can be recovered by concentrating methods without resort to pressure leaching or other chemical treatment.
gabbro	A dark, coarse-grained igneous rock
Galena	Lead sulfide, the most common ore mineral of lead.
Gangue	Worthless rock or other material in which valuable minerals are found.
Geophysical Survey	Indirect methods of investigating the subsurface geology using the applications of physics including electric, gravimetric, magnetic, electromagnetic, seismic, and radiometric principles.
Geophysics	A term to describe exploration methods that use the physical (seismic, gravimetric) or electro resistive characteristics of potential orebodies. Geophysical methods are used to attempt to discover new ore or extensions to known orebodies.
Geostatistics	A sub sector of statistical theory that specializes in natural materials.
Gold Equivalent	Gold plus silver expressed in equivalent ounces of gold using a conversion ratio dependent on prevailing gold and silver prices.
Grab Sample	A sample from a rock outcrop that is assayed to determine if valuable elements are contained in the rock. A grab sample is not intended to be representative of the deposit, and usually the best-looking material is selected.
Grade	the amount of valuable material in a specific volume of rock; typically expressed as grams per tonne for precious metals and as a percentage for base metals.
Gravity separation	recovery of gold from crushed rock or gravel using gold’s high specific gravity to separate it from lighter material
Hanging Wall	The wall or the rock on the upper side of a vein or ore deposit.
Head Grade	The average grade of ore fed into a mill.
Heap LeachingÂ	A process whereby valuable metals (usually gold and silver) are leached from a heap, or pad, of crushed ore by leaching solutions percolating down through the heap and are collected from a sloping, impermeable liner below the pad.Â
Hectare	an area of land equivalent to 10,000 square meters or 2.47 acres.
Hedge Book	A term used to describe a firm’s full array of agreements and derivative products in place to guard against declines in the sales price of gold the company produces. These may include forward sales, puts, calls, or lease rate swaps.
hedging	the effective offsetting of a price or exchange risk inherent in another transaction or arrangement
High Grade	Rich ore. As a verb, it refers to the selective mining of the best or highest grade ore in a mineral deposit.
Host Rock	The rock surrounding an ore deposit.
Hydro Metallurgy	The treatment of ore by wet processes (e.g., leaching) resulting in the solution of a metal and its subsequent recovery.
hydrothermal	pertaining to heated water which transports minerals in solution
igneous rocks	Rocks formed by the solidification of molten material from far below the earth’s surface.
induced polarization	A method of ground geophysical surveying employing an electrical current to determine indications of mineralization.
Inferred Resources	Mineralization which does not have demonstrated economic viability.
In-fill drilling	drilling within a group of previously drilled holes to provide a closer spaced pattern to define more accurately the parameters of the orebody
IntrusiveÂ	A body of igneous rock formed by the consolidation of magma intruded into other rocks, in contrast to lavas which are extruded upon the surface.Â It is through intrusion ofÂ magma that porphyry deposits are formed.Â
Lagging	Planks or small timbers placed between steel ribs along the roof of a stope or drift to prevent rocks from falling, rather than to support the main weight of the overlying rocks.
Leach pad	A large, impermeable foundation or pad used as a base for ore during heap leaching. The pad prevents the leach solution from escaping out of the circuit.
LeachingÂ	A chemical process for the extraction of valuable minerals from ore: also, a natural process by which ground waters dissolve minerals, thus leaving the rock with a smaller proportion of some of the minerals than it contained originally.Â
Lens	Generally used to describe a body of ore that is thick in the middle and tapers towards the ends.
Level	The horizontal openings on a working horizon in a mine; it is customary to work mines from a shaft, establishing levels at regular intervals, generally about 50 meters or more apart.
Limestone	A bedded, sedimentary deposit consisting chiefly of calcium carbonate.
Lode	A mineral deposit in solid host rock.
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 may be backfilled with waste rock.
Low sulfadation ore	Gold ore with a low sulphur content. This is helpful in that the resulting tailings are unlikely to contribute acidic waters leading to acid rock drainage.
Mark-to-Market (MTM)	A term used to refer to the unrealized gain or loss of a company’s hedge book.
Merrill-Crowe	A precipitation process to recover precious metals using zinc dust to treat a deoxygenated precious metals-cyanide solution. This is most applicable to ores with higher silver content.
Metallurgy	A general term embracing the practice and science of extracting metals from their ores and the refining of crude metal.
Metamorphic Rocks	Rocks which have undergone a change in texture or composition as the result of heat and/or pressure.
Mill	A processing plant that produces a concentrate of the valuable minerals or metals contained in an ore deposit. The concentrate must then be treated in some other type of plant, such as a smelter, to affect recovery of the pure metal.
Milling Ore	Ore that contains sufficient valuable mineral to be treated by the milling process.
Mineable Reserves	Ore reserves that are known to be extractable using a given mining plan.
Mineral Resource - measured	a “measured mineral resources” is that part of a Mineral Resource for which quanity, grade or quality, densities, shape, physical characteristics are so well established that they can be estimated with confidence sufficient to allow the appropriate application of technical and economic parameters, to support production planning and evaluation of the economic viability of the deposit. The estimate is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough to confirm both geological and grade continuity.
Mineral Resource - indicated	an “indicated mineral resourse” is that part of a Mineral Resource for which quantity, grade or quality, densities, shape, and physical characteristics, can be estimated with a level of confidence sufficient to allow the appropriate application of technical and economic parameters, to support mine planning and evaluation of the economic viability of the deposit. The estimate is based on detailed and reliable exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough to confirm both geological and grade continuity.
Mineral Resource - inferred	an “inferred mineral resources” is that part of a Mineral Resource for which quantity, grade or qualitycan be estimated on the basis of geological evidence and limited sampling and reasonably assumed, but not verified, geological and grade continuity. The estimate is based on limited information and sampling gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes.
Mineral Resource	A deposit or concentration of natural, solid, inorganic or fossilized organic substance in such quantity and at such grade or quality that extraction of the material at a profit is currently or potentially possible.
Mineralization	The presence of economic minerals in a specific area or geological formation.
Mineralized Material or Deposit	A mineralized body which has been delineated by appropriate drilling and/or underground sampling to support a sufficient tonnage and average grade of metal(s). Under SEC standards, such a deposit does not qualify as a reserve until a comprehensive evaluation, based upon unit cost, grade, recoveries, and other factors, conclude economic feasibility.
Mineralized zone	Any mass of host rock in which minerals of potential commercial value occur.
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.
Molybdenum [Mo]Â	Molybdenum is an element often found in copper porphyry deposits.Â It is used extensively in steels particularly grinding steels and as a filament material.Â Â
Muck	Ore or rock that has been broken by blasting.
Native Metal	A metal occurring in nature in pure form, uncombined with other elements.
Net Profit Interest	A portion of the profit remaining after all charges, including taxes and bookkeeping charges (such as depreciation) have been deducted.
Net Smelter Return	A share of the net revenues generated from the sale of metal produced by a mine.
Open-pit MiningÂ	Open-pit mining is the most common method mining porphyry copper and these open pits account for some of the largest man made holes in the world.Â When determining the size of an open pit the normal ratio is 50% of the shortest distance across.Â In other words if a deposit is 800 ft long by 600 ft wide, the pit can be 300 feet deep.Â This is because the ramps need to be wide enough to allow large trucks to go up and down.Â The open pit mine is the least expensive kind, and it is every developer’s first choice where an orebody is situated close to the surface, is big enough and has little overburden.
Ore	Material that can be mined and processed at a positive cash flow.
Ore Pass	A vertical or sub-vertical hole in which ore is tipped normally through a large grid or “grizzly”. Ore falls down this hole and is collected sometimes after crushing for hoisting to surface.
Ore Reserves	The calculated tonnage and grade of mineralization which can be extracted profitably; classified as possible, probable and proven according to the level of confidence that can be placed in the data.
Orebody	A natural concentration of valuable material that can be extracted and sold at a profit.
Oreshoot	The portion, or length, of a vein or other structure, that carries sufficient valuable mineral to be extracted profitably.
Ounces	weight of gold with a fineness of 999.9 parts per 1,000; 1 Troy ounce is equal to 31.1034 grams
OutcropÂ	An exposure of rock or mineral deposit that can be seen on surface.Â
Overburden	The alluvium and rock that must be removed in order to expose an ore deposit.
Oxidation	A chemical reaction caused by exposure to oxygen that results in a change in the chemical composition of a mineral.
Oxide Ore	Ore in which some or all 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. Oxidation tends to improve gold recovery.
Participating Interest	A company’s interest in a mine, which entitles it to a certain percentage of profits in return for putting up an equal percentage of the capital cost of the project.
Pillar	A block of solid ore or other rock left in place to structurally support the shaft, walls or roof of a mine.
Placer	A sedimentary deposit of minerals concentrated by natural mechanical processes, usually involving moving water in which the dense minerals sink.
Placer Deposit	A deposit of sand or gravel that contains particles of gold, gemstones, or other heavy minerals of value. The common types are stream gravels and beach sands.
Placer Gold	Gold occurring in more or less coarse grains or flakes and obtainable by washing the sand, gravel, etc., in which it is found. Also called alluvial gold.
Placer Mining	The extraction of heavy minerals from a placer deposit by concentration in running water. It includes ground sluicing, panning, shoveling gravel into a sluice, scraping by power scraper and excavation by dragline, dredge or other mechanized equipment.
Porphyry	Igneous rock composed of large, conspicuous crystals (phenocrysts) and a groundmass in which the phenocrysts are embedded. This rock can be a host for large copper and gold deposits. Porphyry gold and copper gold deposits tend to be big and amenable to large-scale mechanized mining.
Porphyry copper deposit	A disseminated large-tonnage, low-grade deposit, in which the copper minerals occur as discrete grains and veins throughout a large volume of rock.
Precambrian Shield	The oldest, most stable regions of the Earth’s crust, the largest of which is the Canadian Shield.
Precipitate	a mixture of mineral particles filtered from solutions as a result of a chemical reaction
Pre-Feasibility Study	A pre-feasibility study is a comprehensive study of the viability of a mineral project that has advanced to astage where the mining method has been established, and which, if an effective method of mineral processing has been determined, includes a financial analysis based on reasonable assumptions of technical, engineering, operating, economic factors and the evaluation of other relevant factors which are sufficient for a qualified person, acting reasonably, to determine if all or part of the mineral resource may be classified as a mineral reserve.
Probable Reserves	Resources for which tonnage and grade and/or quality are computed primarily from information similar to that used for proven reserves, but the sites for inspection, sampling and measurement are farther apart or are otherwise less adequately spaced. The degree of assurance, although lower than that for proven reserves, is high enough to assume continuity between points of observation.
Proven and Probable Mineral Reserves	Reserves that reflect estimates of the quantities and grades of mineralized material at a mine which the Company believes could be recovered and sold at prices in excess of the cash cost of production. The estimates are based largely on current costs and on projected prices and demand for such mineralized material. Mineral reserves are stated separately for each such mine, based upon factors relevant to each mine. Proven and probable mineral reserves are based on calculations of reserves provided by the operator of a property that have been reviewed but not independently confirmed by the Company. Changes in reserves represent general indicators of the results of efforts to develop additional reserves as existing reserves are depleted through production. Grades of ore fed to process may be different from stated reserve grades because of variation in grades in areas mined from time to time, mining dilution and other factors. Reserves should not be interpreted as assurances of mine life or of the profitability of current or future operations.
Proven Reserves	Resources for which tonnage is computed from dimensions revealed in outcrops, trenches, workings or drill holes and for which the grade and/or quality is computed from the results of detailed sampling. The sites for inspection, sampling and measurement are spaced so closely and the geologic character is so well defined that size, shape, depth and mineral content of reserves are well established. The computed tonnage and grade are judged to be accurate, within limits which are stated, and no such limit is judged to be different from the computed tonnage or grade by more than 20%.
pyrite	A yellow iron sulphide mineral, normally of little value. It is sometimes referred to as “fool’s gold”.
Raise	A vertical or inclined underground working that has been excavated from the bottom upward.
Rake	The trend of an orebody along the direction of its strike.
Ramp	An inclined underground tunnel which provides access for exploration or a connection between levels of a mine.
Reagent	a chemical used in the mineral recovery process
Reclamation	The process by which lands disturbed as a result of mining activity are reclaimed back to a beneficial land use. Reclamation activity often 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	The percentage of valuable metal in the ore that is recovered by metallurgical treatment.
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 crude metal from the smelting process.
Refractory Ore	Gold ores in which the gold is not amenable to recovery by conventional cyanide methods without any pre-treatment. The refractory nature can result from either silica or sulphide encapsulation of the gold. Alternatively it can result from the presence of naturally occurring carbon, which reduces gold recovery.
Replacement Ore	Ore formed by a process during which certain minerals have passed into solution and have been carried away, while valuable minerals from the solution have been deposited in the place of those removed.
Reserves - proven	Proven ore â€“ 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.
Reserves - probable	Probable ore â€“ 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.
Reserves - possible	Possible ore â€“ material for which quantitative estimates are based largely on broad knowledge of the geological characteristics of the deposit and for which there are few samples or measurements.
Resource	The calculated amount of material in a mineral deposit, based on limited drill information.
resource - indicated	the estimated grade and quantity for that part of a deposit for which grade continuity, shape and extent has been established for reliable grade and tonnage estimation
resource - inferred	the estimated grade and quantity determined from limited sampling but sufficient geological information and understanding to outline a deposit of potential economic merit
resource - measured	the estimated grade and quantity for that part of a deposit configuration which has been very well established by observation, sampling, drilling trenches and mine workings
resource calculation	Resources are naturally occurring concentrations of minerals in the earth’s crust in such concentrations and structures that extraction is potentially economically feasible. A National Instrument 43-101 resource calculation means that an independent, qualified person has visited the property, reviewed the historical data, and calculated estimates of the project’s mineral resource.
Rock Mechanics	The study of the mechanical properties of rocks, which includes stress conditions around mine openings and the ability of rocks and underground structures to withstand these stresses.
Rockbolting	The act of supporting openings in rock with steel bolts anchored in holes drilled especially for this purpose.
Room-and-Pillar Mining	A method of mining flat-lying ore deposits in which the mined-out area, or rooms, are separated by pillars of approximately the same size.
Rotary Drill	A machine that drills holes by rotating a rigid, tubular string of drill rods to which is attached a bit. Commonly used for drilling large-diameter blast holes in open pit mines.
Royalty	An amount of money paid at regular intervals by the lessee or operator of an exploration or mining property to the owner of the ground. Generally based on a certain amount per ton or a percentage of the total production or profits. Also, the fee paid for the right to use a patented process.
Sample	A small portion of rock or a mineral deposit, taken so that the metal content can be determined by assaying.
Scoping StudyÂ	A scoping study is the first level of study that is performed on a mineral deposit to determine its economic viability.Â This is usually performed to determine whether the expense of a full pre-feasibility study and later full feasibility study is warranted.Â Much can be determined from a scoping study.Â A proper scoping study must be performed by independent engineers.Â
Secondary EnrichmentÂ	Secondary Enrichment refers to the process whereby a vein or mineral deposit has been enriched by minerals that have been taken into solution from one part of the vein or adjacent rocks and re-deposited in another.Â Secondary enrichment usually results in higher concentrations of ore although this is not always the case.Â
Shaft	A vertical or steeply 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 personnel and materials.
Shear or Shearing	The deformation of rocks by lateral movement along numerous parallel planes, generally resulting from pressure and producing such metamorphic structures as cleavage and schistosity.
Shrinkage Stoping	A stoping method which uses part of the broken ore as a working platform and as support for the walls of the stope.
Skarn	the metamorphic rocks surrounding an igneous intrusive where the latter has come in contact with limestone or dolomite rocks
Smelting	A metallurgical operation in which metal is separated from impurities by a process that includes fusion. This is a common intermediate process where an ore concentrate is produced.
Social license	A term used to describe the relationship a mining company has with its neighbours in countries where it operates. This has come to include the miners’ responsibility to minimize the environmental impact of a mining project, and to maximize the economic/social benefit of the project for its in-country partners. Â Â
Sphalerite	A zinc sulphide mineral; the most common ore mineral of zinc.
Spot price	current delivery price of a commodity traded in the spot market, also called the cash price
Step-out Drilling	Holes drilled to intersect a mineralized horizon or structure along strike or down dip.
stock work veining	Densely distributed veining
Stockpile	Broken ore heaped on the surface, pending treatment or shipment.
stockwork	a 3-dimensional network of veins or veinlets
Stope	An underground excavation from which ore has been extracted either above or below mine level.
Stratigraphy	Strictly, the description of bedded rock sequences; used loosely, the sequence of bedded rocks in a particular area.
Strike	The strike of a linear orebody is the direction of the longest dimension of the orebody, for example northeast to southwest.
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, or sometimes the number of tons of rock to be moved per ounce of gold, used in connection with open pit mining.
Sublevel	A level or working horizon in a mine between main working levels.
Sulphide Ore	Sulphide ore will normally represent primary ore. Gold can be simple coatings on sulphide granules and amenable to simple cyanide leaching. Or gold can be intimately mixed with, for example, iron sulphides requiring autoclaving or roasting to extract gold.
Supergene EnrichmentÂ	A mineral deposition process in which near-surface oxidation produces acidic solutions that leach metals, carry them downward, and re-precipitate them, thus enriching sulfide minerals already present.Â Copper sulphides are soluble and therefore the upper part of the orebody may be oxidized and generally leached of many of its valuable elements right down to the water table.Â This is called the zone of oxidation.Â Generally the bulk of dissolved material is carried on down to the zone of supergene enrichment.
Tailings	The material that remains after all metals considered economic have been removed from ore during milling or heap leaching.
Tailings Dam	A natural or man-made area suitable for depositing the material that remains after the treatment of ore.
Tailings Pond	A low-lying depression used to confine tailings, the prime function of which is to allow enough time for heavy metals to settle out or for cyanide to be destroyed before water is discharged into the local watershed.
Ton	means a short ton (2000 pounds)
Tonne	means a metric tonne (2204.6 pounds)
Trend	The direction, in the horizontal plane, or a linear geological feature (for example, an ore zone), measured from true north.
Troy Ounce	Troy ounce of a fineness of 999.9 parts per 1,000 parts, equal to 31.1034 grams.
Tuffs	Ash-flow tuffs are consolidated deposits of volcanic ash, which were emplaced by flowage of a turbulent mixture of gas and pyroclastic materials. Ash-flow deposits consist principally of glass shards and pumice fragments that are usually less than 0.15 inch in length, although some flows consist of ejecta of larger size.
Vein	A tabular geological feature, normally much longer than its width, where chemical or physical differences between it and the surrounding rock have caused economic mineral to concentrate. The vein or reef can be a little or extremely discontinuous and can contain higher-value payshoots.
Wall Rocks	Rock units on either side of an orebody. The hanging-wall and footwall rocks of an orebody.
Zone of Oxidation	The portion of an orebody that has been oxidized, usually in the upper portion of the ore zone.

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