Glosario términos de mina

Glossary of terms

Mining terms
BIF: Banded Ironstone Formation. A chemically formed iron-rich sedimentary rock.

Development: The process of accessing an orebody through shafts and/or tunnelling in underground mining operations.

Diorite: An igneous rock formed by the solidification of molten material (magma).

By-products: Any products that emanate from the core process of producinggold, including silver, uranium and sulphuric acid. Electro-winning: A process of recovering gold from solution by means of electrolytic chemical reaction into a form that can be Calc-silicate rock: A metamorphic rock consisting mainly of calcium-bearing silicates such as diopside and wollastonite, and formed by metamorphism of impure limestone or dolomite. Elution: Recovery of the gold from theactivated carbon into solution before zinc precipitation or electro-winning. Carbon-in-leach (CIL): Gold is leached from a slurry of gold ore with cyanide in agitated tanks and adsorbed on to carbon granules in the same circuit. The carbon granules are separated from the slurry and treated in an elution circuit to remove the gold. Grade: The quantity of gold contained within a unit weight ofgoldbearing material generally expressed in ounces per short ton of ore (oz/t), or grams per metric tonne (g/t). Carbon-in-pulp (CIP): Gold is leached conventionally from a slurry of gold ore with cyanide in agitated tanks. The leached slurry then passes into the CIP circuit where carbon granules are mixed with the slurry and gold is adsorbed on to the carbon. The granules are separated from the slurryand treated in an elution circuit to remove the gold. Indicated Mineral Resource: An ‘Indicated Mineral Resource’ is that part of a Mineral Resource for which tonnage, densities, shape, physical characteristics, grade and mineral content can be estimated Comminution: Comminution is the crushing and grinding of ore to make gold available for treatment. (See also “Milling”). with a reasonable level ofconfidence. It is based on exploration, sampling and testing information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings Contained gold: The total gold content (tons multiplied by grade) of and drill holes. The locations are too widely or inappropriately spaced the material being described. to confirm geological and/or grade continuity but arespaced closely Cut-off Grade (Surface Mines): The minimum grade at which a unit of ore will be mined to achieve the desired economic outcome. Inferred Mineral Resource: An ‘Inferred Mineral Resource’ is that Depletion: The decrease in quantity of ore in a deposit or property resulting from extraction or production. part of a Mineral Resource for which tonnage, grade and mineral content can beestimated with a low level of confidence. It is inferred from geological evidence and assumed but not verified geological enough for continuity to be assumed. Greenschist: A schistose metamorphic rock whose green colour is due to the presence of chlorite, epidote or actinolite. smelted easily into gold bars.

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and/or grade continuity. It isbased on information gathered through appropriate techniques from locations such as outcrops, trenches, pits, workings and drill holes which may be limited or of uncertain quality and reliability.

Mineral deposit: A mineral deposit is a concentration (or occurrence) of material of possible economic interest in or on the Earth’s crust.

Mineral Resource: A ‘Mineral Resource‘ is aconcentration or Leaching: Dissolution of gold from crushed or milled material, including reclaimed slime, prior to adsorption on to activated carbon. occurrence of material of intrinsic economic interest (in or on the Earth’s crust) in such form, quality and quantity that there are reasonable prospects for eventual economic extraction. The Life of mine (LOM): Number of years that the operation is planning...