Glossary of terms

Definition
Auger drill An auger drilled hole uses a rotating screw blade acting as a screw conveyor to remove the drilled material out of the hole.
Block width The average width at which it is estimated a block of ore will be mined.
Clastic Pertaining to a rock or sediment composed principally of broken fragments that are derived from pre-existing rocks or minerals by the processes of weathering and erosion, and have been transported some distance from their place of origin.
Cut-off grade The lowest grade of mineralised rock which determines as to whether or not it is economic to recover its gold content by further concentration.
Diamond drill Diamond drilling uses a diamond encrusted drill bit to drill through the rock and recovers a solid core, for examination on the surface.
Dilution Waste or material below the cut-off grade that contaminates the ore during the process of mining operations and thereby reduces the average grade mined.
Destress By mining a two-metre slice through the package in an optimal position to ensure a destressed window of 50 to 60 metres above or below the associated stope.
Gold equivalent ounces A quantity of metal (such as copper) converted to an amount of gold in ounces, based on accepted gold and other metal prices, i.e. the accepted total value of the metal based on its weight and value thereof divided by the accepted value of one troy ounce of gold.
Indicated Mineral Resource That part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a reasonable level of confidence. It is based on information from exploration, sampling and testing of material gathered from locations such as outcrops, trenches, pits, workings and drill holes. The locations are too widely or inappropriately spaced to confirm geological and/or grade continuity but are spaced closely enough for continuity to be assumed.
Inferred Mineral Resource That part of a Mineral Resource for which tonnage, grade and mineral content can be estimated with a low level of confidence. It is inferred from geological evidence and sampling and assumed but not verified geologically or through analysis of grade continuity. It is based on information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes that may be limited or of uncertain quality and reliability.
Intracratonic basin Refers to a basin on top of a craton, which is part of the earth's crust that has attained stability and has been little deformed for a prolonged period.
Kriging efficiency (KE) Provides a measure of the reliability of block evaluations.
Lacustrine Produced by or formed within a lake or lake environment.
Life-of-mine (LoM) Number of years that an operation is planning to mine and treat Proved and Probable Reserves, based on the current mining plan. Year one of this plan is referred to as the Operational Plan.
Littoral Pertaining to the zone between the highest and lowest levels of spring tides known as the fore-beach.
Measured Mineral Resource That part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated with a high level of confidence. It is based on detailed and reliable information from exploration, sampling and testing of material from locations such as outcrops, trenches, pits, workings and drill holes. The locations are spaced closely enough to confirm geological and grade continuity.
Mine call factor The ratio expressed as a percentage which the specific product accounted for in 'recovery plus residue' bears to the corresponding product 'called for' by the mine's measuring and evaluation methods.
Mineral Reserve The economically mineable material derived from a Measured and/or Indicated Mineral Resource. It is inclusive of diluting and contaminating materials and allows for losses that are expected to occur when the material is mined. Appropriate assessments to a minimum of a pre-feasibility study for a project and an LoM plan for an operation must have been completed, including consideration of and modification by, realistically assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors (the modifying factors). Such modifying factors must be disclosed.
Mineral Resource A concentration or occurrence of material of economic interest in or on the earth's crust in such form, quality and quantity that there are reasonable and realistic prospects for eventual economic extraction. The location, quantity, grade, continuity and other geological characteristics of a Mineral Resource are known, or estimated from specific geological evidence, sampling and knowledge interpreted from an appropriately constrained and portrayed geological model. Mineral Resources are subdivided, and must be so reported, in order of increasing confidence in respect of geoscientific evidence, into Inferred, Indicated and Measured categories.
Net Smelter Return (NSR) Is defined as the return from sales of concentrates expressed in US$/tonne,
i.e.: NSR = (Au price-Au selling costs) x Au grade x Au recovery + (Cu price-Cu selling price) x Cu grade x Cu recovery.
Operational Plan Year one of the LoM plan.
Pay limit The value at which it is estimated that ore can be mined at break-even.
Peneplain A low, nearly featureless, gently undulating land surface of considerable area, which has been produced by the processes of long continued sub-aerial erosion.
Plant recovery factor The ratio, expressed as a percentage, of the mass of the specific mineral product actually recovered from ore treated at the plant to its total specific mineral content before treatment.
Probable Mineral Reserve Economically mineable material derived from a Measured or Indicated Mineral Resource or both. It is estimated with a lower level of confidence than a Proved Mineral Reserve. It includes diluting and contaminating materials and allows for losses that are expected to occur when the material is mined. Appropriate assessments to a minimum of a pre-feasibility study for a project or an LoM plan for an operation must have been carried out, including consideration of and modification by, realistic assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. Such modifying factors must be disclosed.
Proved Mineral Reserve Economically mineable material derived from a Measured Mineral Resource. It is estimated with a high level of confidence. It includes diluting and contaminating materials and allows for losses that are expected to occur when the material is mined. Appropriate assessments to a minimum of a pre-feasibility study for a project or an LoM plan for an operation must have been carried out, including consideration of and modification by, realistic assumed mining, metallurgical, economic, marketing, legal, environmental, social and governmental factors. Such modifying factors must be disclosed.
Regolith Is a layer of loose unconsolidated rock that lies above a layer of bedrock.
Tonnage discrepancy Difference between the tonnage hoisted as ore and that accounted for by the plant measuring methods. Discrepancy is referred to as a shortfall when the calculated tonnage is less than the tonnage accounted for by the plant, or an excess when the opposite occurs.
Tonne(s) Metric ton (tonnes) = 1,000 kilograms.
Uraninite A strongly radioactive, brownish-black mineral, UO2, forming the chief ore of uranium (U3O8) and containing variable amounts of radium, lead, thorium and other elements as impurities.
Witwatersrand Basin A sedimentary basin in South Africa that contains close to a 6,000 metre thick sequence of principally argillaceous and arenaceous sediments with inter-bedded conglomerates.