| activated carbon |
chemically treated and heated carbon which has the ability to absorb gold |
| alloy |
metal prepared by adding other metals or non-metals to a basic metal to secure desirable properties |
| alteration |
the physical or chemical change in the composition of rock |
| arsenopyrite |
iron arsenic sulphide, FeAsS |
| autoclave |
a closed strong vessel for conducting chemical reactions under high pressure and temperature |
| backfill |
waste rock or tailings used to fill mined out areas, particularly underground |
| ball mill |
a rotating horizontal cylinder in which ore is ground using various types of grinding media including iron balls |
| basalt |
dark colored, fine-grained volcanic igneous rock |
| base metal |
non-ferrous metals inferior in value to precious metals; i.e. copper lead, zinc, nickel |
| bedrock |
solid rock beneath superficial soil cover and unconsolidated sediments |
| belt |
an exposed zone or band of a particular kind of rock |
| bioxidation |
the oxidation of elements caused by naturally occurring bio-organisms in rock. Bioxidation is used in the recovery of gold from sulhpide rock by providing the optimum temperature, acidity (pH) and oxygen levels for the natural oxidation process to work most effectively |
| blast-hole stoping |
an underground mining method by which ore is extracted using large diameter holes for blasting |
| breccia |
rock consisting of fragments, more or less angular, in a matrix of finer-grained material or of cementing material |
| breccia pipe |
a pipe or funnel shaped structure filled with angular fragments held together with a fine grained cement. The feature may be formed in a variety of ifferent ways. It is likely to be a hydrothermal or explosion-induced pipe in which fluids have deposited ore-forming minerals |
| bullion |
the product of smelting or refining precious metals, usually in the form of bars or ingots |
| by-product |
revenue, net of transportation, refining and treatment charges, from the sale of metals derived in conjunction with the production of the primary mine metal |
| carbide |
compound of carbon with one or more metallic elements |
| carbon circuit |
activated carbon is used to collect gold from the leach dump solution and a chemical process is subsequently used to recover gold from the carbon |
| carbon steel |
iron-based alloy containing only residual quantities of elements other than carbon |
| carbonaceous |
containing carbon or coal, especially shale or other rock containing small particles of carbon distributed throughout the whole mass |
| carbon-in-leach ("CIL") process |
this process is used to recover gold into activated carbon during the agitation leach process. The gold recovery from carbon follows normal carbon stripping procedures. This process is used to improve gold recoveries when naturally occurring carbonaceous materials are present in the ore which reduce normal gold recoveries |
| carbon-in-pulp ("CIP") process |
this process is used to recover gold that has been dissolved after cyanide leach agitation. Pulp, after cyanidation, is mixed in a series of agitators with coarse activated carbon particles. Carbon is moved counter-current to the pulp, absorbing gold as it passes through the circuit. Loaded carbon is removed by screening from the lead agitated tank. Gold is recovered from the loaded carbon by stripping at elevated temperature and pressure in a caustic cyanide solution. This high-grade solution is then passed through an electrolytic cell, where gold powder is deposited on a stainless steel woven wire cathode. The gold powder is washed from the loaded cathodes and then smelted to produce doré |
| cash cost |
includes production costs, royalties, marketing and refining charges, together with all administration expenses at the operating level |
| cathode |
the electrode of an electrochemical cell at which reduction occurs |
| cemented carbides |
powdered metallurgical products consisting of a carbide of niobium, for example, in a metal matrix, usually cobalt or nickel |
| chlorite |
platey iron-magnesium silicate, typically formed during alteration by other minerals at low temperatures |
| circulating fluid bed roaster |
a furnace in which finely ground ore or concentrate is roasted to eliminate sulfur |
| columbite |
niobium bearing mineral (Fe,Mn)(Nb,Ta)2O6 containing 40-75% Nb2O5, 1-40% Ta2O5, 0.5-3% TiO2, 10-20% Fe |
| columbite-tantalite |
niobium bearing mineral (Fe,Mn)(Nb,Ta)2O6 containing 25-60% Nb2O5, 20-50% Ta2O5, 0.5-3% TiO2, 10-20% Fe |
| concentrate |
a product containing the valuable metal and from which most of the waste material in the ore has been eliminated |
| concentrator |
a plant for recovery of valuable minerals from ore in the form of concentrate. The concentrate must then be treated in some other type of plant, such as a smelter, to effect recovery of the pure metal |
| cut-and-fill stoping |
an underground mining method in which the ore is excavated by successive flat slices, working upward from the level. After each slice is blasted, all broken ore is removed and the stope is filled with waste up to within a few feet of the back before the next slice is taken out |
| cut-off grade |
the lowest grade of mineral resources considered economic; used in the calculation of reserves in a given deposit |
| cyanidation |
a method of extracting gold or silver by dissolving it in a weak solution of sodium or potassium cyanide |
| cyanide-leaching |
dissolving gold or silver in a weak solution of sodium cyanide or potassium cyanide |
| dilution |
an estimate of the amount of waste or low-grade mineralized rock which will be mined with the ore as part of normal mining practices in extracting an orebody |
| diorite |
an intrusive rock of magnatic origin |
| dip |
the angle of incline from horizontal of a planar feature, such as an orebody |
| disseminated ore |
ore bearing small particles of valuable minerals spread throughout the rock |
| dolerite |
intrusive dyke rock made up mostly of feldspar and pyroxene |
| doré |
unrefined gold and silver bars usually containing more than 90% precious metal |
| drift-and-fill |
an underground mining method whereby ore is mined by drifting along the mineralization and backfilling the void so that the next level can be mined |
| dyke |
an igneous intrusion which cuts across the bedding of other planar structures in the country rock |
| electrowinning |
recovery of a metal from an ore by means of electro-chemical processes |
| erosion |
the alteration, loosening and removal of land surface material by the actions of running water and wind |
| extrusive |
igneous rock which has been erupted to the surface by volcanic activity |
| facies |
distinctive rock type |
| fault |
a break in the sub-surface strata where there is displacement relative to the original position of strata |
| 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 |
| first aid |
all work related injury or illness that does not require medical attention |
| flotation |
a milling process by which some mineral particles are induced to become attached to bubbles of froth and float, and others to sink, so that the valuable minerals are concentrated and separated from the gangue |
| fold |
a curve or bend of a planar structure such as a rock bed or a fault plane. The result of deformation processes in the earth's crust |
| footwall |
the mass of rock beneath a geological structure (orebody, fault, etc.) |
| formation |
a unit of geological mapping, consisting of a large and persistent stratum of rock |
| gabbro |
coarse-grained igneous rock containing minor silica |
| 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 |
| granodiorite |
a plutonic rock consisting of quartz, calcic oligoclase or andesine and orthoclase with biotite, hornblende or pyroxene as mafic constituents |
| granophyric |
an igneous texture characterized by irregular intergrowths of quartz and feldspar |
| gravity separation |
recovery of gold from crushed rock using gold's high specific gravity to separate it from lighter material |
| greenstone |
a metamorphic (cooked) rock whose green colour is due to the presence of chlorite, epidote or actinolite. Commonly a loose term used to describe deformed, recrystallized volcanic and/or sedimentary rock which has a high amphibole content as a result of its original bulk composition |
| hanging wall |
the mass of rock above a geological structure (orebody, fault, etc.) |
| headframe |
the framework building at the top of the shaft which houses the hoisting mechanisms |
| hedging |
the effective offsetting of a price or exchange risk inherent in another transaction or arrangement |
| high-performance alloy |
designed to function for extended periods of time in highly corrosive environments above 650ºC |
| high-strength, low alloy steel (HSLA) |
iron-based alloy whose strength is achieved by adding moderate levels of alloying elements such as Nb, Va, and Ti |
| host rock |
the rock containing minerals, i.e. an orebody |
| hydrometallurgy |
the selective dissolution of metals from ore to concentrates |
| hydrothermal |
pertaining to heated water which transports minerals in solution |
| igneous rock |
rock which is magmatic in origin |
| indicated mineral resource |
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 and test information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that are spaced closely enough for geological and grade continuity to be reasonably assumed |
| infill drilling |
drilling between previously drilled holes to provide additional geological information to more accurately define mineralization |
| ingot |
a mass of metal cast into a convenient shape for storage or transportation to be later processed |
| intrusive |
rock which while molten, penetrated into or between other rocks but solidified before reaching the surface |
| ISO 14000 |
international standards for organizations to implement sound environmental management systems |
| ISO 9000 |
international standards for organizations to implement quality management systems and quality assurance programs |
| kriged resource |
resource grades estimated using weighted averages of the surrounding samples. The weights are based on the mineralization spatial continuity which has been statistically quantified before hand |
| lag |
coarse gravel material remaining behind when finer material has been eroded away |
| lava |
molten magma extruded from volcanic vent |
| leach/heap leach |
to dissolve minerals or metals out of ore with chemicals. Heap leaching gold involves the percolation of a cyanide solution through crushed ore heaped on an impervious pad or base |
| long-hole stoping |
this underground method of stoping involves the drilling of blast holes generally exceeding 15 metres in length and is normally only practical for large ore bodies or wide regular veins with strong country rock to minimize waste dilution |
| lost time injury (LTI) |
the number of lost time injuries multiplied by 200,000 and divided by the total number of exposure hours |
| lost time injury incident rate (LTA) |
all work related injuries or illnesses where the employee cannot work the next regular scheduled shift |
| mafic |
igneous rock with dark coloration due to high magnesium and iron content |
| measured mineral resource |
is that part of a mineral resource for which quantity, 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 |
| medical injury |
any injury that requires treatment by a licensed medical professional that does not result in lost time or restricted duty but is beyond first aid |
| Merrill-Crowe precipitation |
a process utilized to recover dissolved gold and silver metals from a sodium cyanide leaching solution. The gold and silver metals are precipitated by zinc dust after the leaching solution is clarified and deoxygenated under vacuum |
| metasediments |
metamorphosed sedimentary rocks |
| metasomatism |
the process by which one mineral is replaced by another |
| mill |
the plant for grinding ore to a fine powder and extracting the economic metals by physical and/or chemical means |
| mineral resource (deposit) |
is a concentration or occurrence of natural, solid, inorganic or fossilized organic material in or on the earth’s crust in such form and quantity and of such a grade or quality that it has reasonable prospects for economic extraction. The location, quantity, grade, geological characteristics and continuity of a mineral resource (deposit) are known, estimated or interpreted from specific geological evidence and knowledge |
| mineralized zone |
host rock in which minerals of potential commercial value occur |
| net smelter return (NSR) |
a share of the net revenue generated from the sale of metal produced by the mine |
| niobium alloy |
based on niobium and alloyed principally with Al, Hf, Sn, Ti, and Zr. Physical properties include high resistance to corrosion, good workability, and high refractoriness |
| niobium oxide (Nb2O5) |
second most important commercial niobium product. Starting material for other specialized niobium products |
| non-refractory ore |
ore which is relatively easy to treat for recovery of the valuable substances |
| open pit |
a mine on the surface |
| ore |
a mixture of minerals, host rock and waste rock which is expected to be profitably mined |
| ore reserve |
is the economically mineable part of a measured or indicated mineral resource demonstrated by at least a preliminary feasibility study. This study must include adequate information on mining, processing, metallurgical, economic and other relevant factors that demonstrate, at the time of reporting, that economic extraction can be justified. An ore reserve includes diluting materials and allowances for losses that may occur when the material is mined |
| ounces |
weight of gold with a fineness of 999.9 parts per 1,000; 1 Troy ounce is equal to 31.1034 grams |
| outcrop |
part of a geological formation or structure that appears at the surface of the earth |
| oxidation |
chemical reaction between any substance and oxygen |
| oxide ore |
mineralized rock in which the minerals have been partially or wholly oxidized by weathering processes |
| paste fill |
back fill which utilizes a large percentage or all of a mine’s tailing (particularly fine fractions), and has low water content |
| porphyry |
igneous rocks containing large crystals in a fine-grained groundmass |
| porphyry dykes |
a tabular body of igneous rock that cuts across the structure of adjacent rocks, and contains conspicuous phenocryst in a fine grained or aphanites ground mass |
| pressure oxidation |
a process of conducting chemical reactions under high pressure and temperature |
| pressure oxidation circuit |
a metallurgical process that uses high pressure and temperature to liberate precious metals from within sulphide concentrates |
| process loss |
any unplanned interruption or downgrading of operating processes resulting from an accident, abuse, negligence, or act of God |
| production cost |
cash cost plus depreciation, amortization and reclamation |
| property damage |
damage occurring to property through an accident, abuse, negligence, or act of God |
| proterozoic rock |
a rock of Proterozoic age, the younger of two Precambrian eons |
| proven reserve |
is the economically mineable part of a measured mineral resource demonstrated by at least a preliminary feasibility study. This study must include adequate information on mining, processing, metallurgical, economic and other relevant factors that demonstrate, at the time of reporting, that economic extraction can be justified |
| pyrite |
an iron sulphide, FeS |
| pyrochlore |
principal niobium bearing mineral (NaCaNb2O6F) containing 40-65% Nb2O5, 0-2% Ta2O5, 1-6% TiO2, 0-2% Fe |
| pyrrhotite |
an iron sulphide, FeS |
| raise |
a vertical or upward inclined drive to connect underground mine levels or to the surface |
| reagent |
a chemical used in the mineral recovery process |
| reclamation |
the rehabilitation to beneficial use of land disturbed by mining activity |
| refractory ore |
gold mineralization encapsulated in silica or sulphide, which is not amenable to cyanide leaching methods |
| refractory rock |
rock which is difficult to treat for recovery of the valuable minerals. Most commonly treated by oxidizing the rock in an autoclave |
| replacement zone |
a locality where a fluid has dissolved some of the primary components of a rock and deposited a set of secondary minerals. These may be ore minerals replacing what would otherwise be waste rock |
| reserve |
that part of a resource that can be profitably mined under current or specified economic conditions. A reserve estimate must consider all technical, operating, legal and financial factors |
| reserve - probable |
the estimated quantity and grade of part of a indicated resource for which all consideration factors establish a confidence level for positive decisions on major expenditures |
| reserve - proven |
the estimated quantity and grade of part of a measured resource for which all consideration factors establish the highest degree of confidence in the estimate |
| resource |
the grade and quantity estimate of a mineralized deposit that indicates mining is currently or potentially profitable under economic and operating conditions |
| 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 |
| rod mill |
similar to a "SAG" mill except that it requires input of finer ore |
| room-and-pillar |
mining method used for flat-lying deposits where the ore is removed in chambers or rooms leaving pillars for support |
| scat |
a coarse particle of rock discharged from the milling process which is often crushed and recycled through the mill |
| schist |
fine-grained metamorphic rock with laminations similar to slate |
| semi-autogenous ("SAG") mill |
a large diameter grinding mill utilizing steel balls and large rock pieces to grind ore from a coarse feed size to a relatively small particle size. The semi-autogenous mill replaces the equipment normally used for fine crushing and rod milling |
| severity measure |
the number of days lost, plus the number of days of restricted duty, multiplied by 200,000 and divided by the number of exposure hours |
| shaft |
a vertical passage in an underground mine used for transporting personnel, equipment, supplies and mined material |
| shear zone |
a tabular zone of rock which has been crushed and brecciated by parallel fractures due to "shearing" along a fault or zone of weakness. These can be mineralized with ore-forming solutions |
| silicic alteration |
replacement of silica |
| spot price |
current price of gold or other commodity traded in the immediate market |
| stainless steel |
iron-based alloy containing at least 10% chromium to confer corrosion resistance |
| stainless steel (austenitic) |
also called 18-8 grades contain from 16% to 26% chromium and 6% to 20% nickel, are not hardenable by heat treatment, and are nonmagnetic in the annealed condition |
| stainless steel (ferritic) |
contain low levels of carbon and up 30% chromium |
| standard-grade ferroniobium (FeNb) |
most important commercial niobium product. Specified to be 63% Nb, but typically 66.5% Nb, with the balance being Fe |
| stockwork |
a 3-dimensional network of veins or veinlets |
| stope |
the working area from which ore is extracted in an underground mine |
| strike |
the direction or bearing of a mineralized vein or rock formation |
| strip (or stripping) ratio |
the tonnage or volume of waste material which must be removed to allow the mining of one tonne of ore in an open pit |
| stripping ratio |
the ratio of the amount of waste rock removed per tonne of ore mined |
| struverite |
niobium bearing mineral (Ti,Ta,Nb,Fe)2O6 containing 12-13% Nb2O5, 12-13% Ta2O5, 56-57% TiO2 |
| sulfide |
a mineral compound characterized by the linkage of sulfur with metal or semimetal; eg galena, PbS, or pyrite, FeS2 |
| sulphides |
compounds of sulphur with other metallic elements |
| superalloy |
see high-performace alloy |
| supergene |
refers to ore or ore minerals that have been formed by the effects (usually oxidization and secondary sulphide enrichment) produced by descending ground water |
| sustainability |
the exploration, design, construction, operation and closure of mines in a manner that respects and responds to the social, environmental and economic needs of present generations and anticipates those of future generations in the communities and countries where we work |
| SX-EW processing |
solvent extraction and electrowinning processing. Recovery of a metal from an ore by means of acid leaching and organic extraction, combined with electro-chemical processes |
| syncline |
a fold of strata forming an inverted arch |
| tailing |
material rejected from a mill after the recoverable valuable minerals have been extracted |
| tantalite |
niobium bearing mineral (Fe,Mn)(Nb,Ta)2O6 containing 2-40% Nb2O5, 42-84% Ta2O5, 0.5-3% TiO2, 10-20% Fe |
| telluride |
a mineral characterized by the linkage of metal with tellurium |
| tholeiitic |
basaltic magma containing little or no olivine |
| tool steel |
iron based alloy with a higher carbon and alloy content. Used to make tools |
| total days lost |
the total number of days an employee was scheduled to work but was unable to as a result of a work related injury or illness |
| total days restricted |
the total number of days an employee cannot do any of a part of normal work activities but does not result in lost time |
| total reportable injury incident rate |
the number of medical injuries, plus the number of restricted duty injuries, plus the number of lost time injuries, plus the number of fatalities, multiplied by 200,000 and divided by the total number of exposure hours |
| tuff |
strata of volcanic ash |
| turbidite |
a marine clastic sediment deposited by sea bed currents laden with suspended material |
| ultrabasic |
igneous rock with very low silica content |
| wall rock |
the rock mass adjacent to a fault, fault zone or lode |
| weathered zone |
near surface zone in which the exposed rock has been chemically or physically changed due to the action of rain, water, etc. |
| zinc precipitation |
see Merrill-Crowe precipitation |
print this page
