Glossary

-A-
Adit -A tunnel driven horizontally into a hillside to provide access to a mineral deposit.

-B-
Backfill - Material used to fill the space in a mine after ore has been extracted.

Block Caving - A mining method that involves creating a cave below the surface, causing the ore to break away from the ceiling and fall to the bottom of the cave. Robots bring the ore to an underground crusher, and shafts convey the ore to the surface for processing.

-C-
Cut-off grade - The lowest grade of mineralized material considered economic; used in the calculation of the ore reserves in a given deposit.

Cyanidation - A method of extracting gold grains from crushed or ground ore by dissolving them in a weak solution of sodium or calcium cyanide-also known as leaching.

-D-
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 a commercially mineable orebody or as containing ore reserves until final legal, technical and economic factors have been resolved.

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 more or less uniformly through the gangue matter; it is distinct from massive ore, wherein the valuable minerals occur in almost solid form with very little waste mineral included.

-F-
Footwall - The mass of rock beneath a geological structure such as an orebody or fault.

Formation - The ordinary unit of geologic mapping consisting of a large and persistent stratum of rock.

-G-
Grinding media - Material used to finely grind ore material to a size that allows recovery of the desired contained material.

-H-
Hanging wall - The mass of rock overlying a geological structure such as an orebody or fault.

-I-
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.

-L-
Leaching - The process in which a soluble metallic compound is extracted from ore by dissolving the metals in a solvent; see cyanidation.

Level - A horizontal opening in a mine; levels are usually established at regular intervals.

-M-
Mineralized zone - Any mass of host rock in which minerals of potential commercial value occurs.

-O-
Ore - Material that contains one or more minerals that can be recovered for a profit.

Ounces - Troy ounces of a fineness of 999.9 parts per 1,000 parts, equal to 31.1034 grams.

-P-
Phyllite - Scaly minerals, micas, chlorites and clays; a term more recently applied to minerals with a layered crystal structure.

Precipitate - A mixture of mineral particles filtered from solutions as a result of a chemical reaction.

-R-
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 includes the removal of buildings, equipment, machinery; 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.

Reserves - That part of a mineral deposit that could be economically and legally extracted or produced at the time of the reserve determination. Reserves are customarily stated in terms of ore when dealing with metalliferous minerals. There are three categories of reserves:

Proven ore ? 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.

Probable ore ? 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.

Possible ore ? 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
There are three categories of resources:

Inferred mineral resource - A mineral resource inferred from geoscientific evidence, drill holes, underground openings, or other sampling procedures where the lack of data is such that continuity cannot be predicted with confidence and where geoscientific data may not be known with a reasonable level of confidence.

Indicated mineral resource - A mineral resource sampled by drill holes, underground openings or other sampling procedures at locations too widely spaced to ensure continuity but close enough to give a reasonable indication of continuity and where geoscientific data are known with a reasonable level of reliability. An indicated mineral resource estimate will be based on more data, and therefore will be more reliable, than an inferred mineral resource estimate. Leads to probable ore reserves.

Measured mineral resource - A mineral resource intersected and tested by drill holes, underground openings and/or other sampling procedures at locations which are spaced closely enough to confirm continuity and where geoscientific data are reliably known. A measured mineral resource estimate will be based on a substantial amount of reliable data, interpretation and evaluation of which allows clear determination to be made of shapes, sizes, densities and grades. Leads to a proven ore reserve.

Run of mine ore - Uncrushed ore in its natural state just as it is when blasted.

-S-
Semi-autogenous mill - A mill in which rock is reduced to smaller particles partially by grinding against other pieces of rock.

Shaft - A vertical passageway to an underground mine for moving personnel, equipment, supplies and material including ore and waste rock.

Spot price - Current delivery price of a commodity traded in the spot market, also called the cash price.

Stope - The working area in a mine from which ore is extracted.

Strike - The direction, or course or bearing, of a vein of rock formation measured on a level surface.

Sulphides - Compounds of sulphur with other metallic elements.

-T-
Tailings - Material rejected from a mill after the valuable minerals have been recovered.

Ton - A short ton (2000 pounds).

Tonne -A metric tonne (2204.6 pounds).

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