Aerial Magnetometer - An instrument used to measure magnetic field strength from an airplane.

Aeromagnetic Survey - A geophysical survey using a magnetometer aboard, or towed behind, an aircraft.

Airborne Survey - A survey made from an aircraft to obtain photographs, or measure magnetic properties, radioactivity etc.

Alluvium - Relatively recent deposits of sedimentary material laid down in river beds, flood plains, lakes, or at the base of mountain slopes.

Assay - A chemical test performed on a sample of ores or minerals to determine the amount of valuable metals contained.

Bulk Sample - A large sample of mineralized rock, frequently hundreds of tons, selected in such a manner as to be representative of the orebody being sampled. Used to determine metallurgical characteristics.

Base Camp - Center of operations from which exploration activity is conducted.

Carat - The standard unit of mass used for diamonds and other precious stones, equal to 0.2 gram.

Claim - A portion of land held either by a prospector or a mining company. In Canada, the common size is 1320 Ft. (about 400M or 40 acres, 16 Hectares)

Cleavage - The tendency of a mineral to split along crystallographic planes.

Core - The long cylindrical piece rock, about an inch in diameter, brought to surface by diamond drilling.

Density - The mass of a substance per unit volume. In resource or reserve estimation, it is expressed in tones per cubic meter or tones per cubic foot. When working with smaller substances, it is more often expressed in grams per cubic centimeter. Also called specific gravity.

Deposit - A body of rock containing valuable minerals; usage is generally restricted to zones of mineralization whose size has been wholly or partly determined through sampling.

Development Drilling - Drilling to establish accurate estimates of mineral reserves.

Diamond - The hardest known mineral, composed of pure carbon; low quality diamonds are used to make bits for diamond drilling in rock.

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.

Dyke - A long and relatively thin body of igneous rock that, while in the molten state, intruded a fissure in older rocks.

Erosion - The breaking down and subsequent removal of either rock or surface material by wind, rain, wave action freezing and thawing and other processes.

Exploration - Prospecting, Sampling, mapping, diamond drilling and other work involved in searching for ore.

EM Survey - A geophysical survey method which measures the electromagnetic properties of rocks.

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.

Feasibility Study - An economic study assessing whether a mineral deposit can be mined profitably, by estimating the capital and operating costs of a mine and the potential revenues from production.

Fissure - An extensive crack, break or fracture in rocks.

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.

Geophysics - The study of the physical properties of rocks and minerals.

Geology - The science concerned with the study of the rocks which compose the earth.

Grade - The concentration of metal or valuable mineral in a body of rock, usually expressed as a percentage or in grams per ton or carats per ton.

Geophysical survey - A scientific method of prospecting that measures the physical properties of rock formations. Common properties investigated include magnetism, specific gravity, electrical conductivity and radioactivity.

Host Rock - The rock surrounding an ore deposit.

Hydrothermal - Relating to hot fluids circulating in the earths crust.

Igneous Rocks - Rocks formed by the solidification of molten material from far below the earths surface.

Intrusion - 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.

Indicated resource - A resource whose size and grade have been estimated from sampling at places spaced closely enough that its continuity can be reasonably assumed.

Jig - A piece of milling equipment used to concentrate ore on a screen submerged in water, either by the reciprocating motion of the screen or by the pulsation of water through it.

Kimberlite - A variety of peridotite; the most common host rock of diamonds.

Lamprophyre - an igneous rock, composed of dark minerals, that occurs in dykes; sometimes contains diamonds.

Logging - The process of recording geological observations of drill core either on paper or on computer disk.

Long Ton - 2240 pounds, avoirdupois, (compared with a short ton, which is 2000 pounds).

Magnetic gradient Survey - A geophysical survey using a pair of magnetometers a fixed distance apart, to measure the difference in the magnetic field with height above the ground.

Microdiamonds - Diamonds with dimensions between 0.1 mm and 0.5 mm are recovered using a caustic fusion dissolution circuit, with samples up to 250 kg in size. The caustic fusion process utilizes systematic rock crushing and complete caustic soda-driven dissolution of the rock at high temperature using a caustic soda. This destroys most of the minerals in the rock, but leaves the diamonds intact for recovery in the observing laboratory.

Macrodiamonds - These diamonds over 0.5 mm in one dimension are recovered from samples up to 50 tonnes in size by processing through a modular, one tonne per hour dense media separation (DMS) plant. This allows kimberlite mini-bulk samples to be evaluated for commercial-sized diamonds more quickly than through the use of the caustic fusion process. Kimberlite samples are crushed, sized and processed to produce concentrates for diamond recovery by the observation laboratory or the x-ray flow sorter.

Magnetic Survey - A geophysical survey that measures the intensity of the earth's magnetic field.

Map Staking - A form of claim staking practiced in some jurisdictions whereby claims are staked by drawing lines around the claim on claim maps at a government office.

Mineral - A naturally occurring homogenous substance having definite physical properties and chemical composition and if formed under favorable conditions, a definite crystal form.

Open Pit - A mine that is entirely on the surface. Also referred to as open cut or open cast mine.

Ore - A mixture of ore minerals and gangue from which at least one of the ore minerals can be extracted at a profit.

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.

Plant - A building in which a process or function is carried out. At a mine site it will include warehouses, hoisting equipment, compressors, maintenance shops and offices.

Primary Deposits - Valuable minerals deposited during the original period of mineralization, as opposed to those deposited as a result of alteration or weathering.

Private Placement - Sale of shares to individuals or corporations outside the normal market, at a negotiated price. Often used to raise capital for a junior exploration company.

Probable Reserves - Valuable mineralization not sampled enough to be termed proven.

Proven Reserves - Reserves that have been sampled extensively by closely spaced diamond drill holes and possibly developed by underground workings in sufficient detail to render an accurate estimation of grade and tonnage.

Resource - The calculated amount of material in a mineral deposit, classified as measured, indicated or inferred, based on the density of drill hole information used.

Reserve - That part of a mineral resource that can be mined profitably.

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 blastholes in open pit mines.

Sample - A small portion of rock or a mineral deposit taken so that the metal content can be determined by assaying.

Sampling - Selecting a fractional but representative part of a mineral deposit for analysis.

Seismic Prospecting - A geophysical method of prospecting, utilizing knowledge of the speed of reflected sound waves in rocks.

Sustainable Development - Industrial Development that does not detract from the potential of the natural environment to provide benefits to future generations.

Shearing - The deformation of rocks by lateral movement along innumerable parallel planes, generally resulting from pressure and producing such metamorphic structures as cleavage.

Trench - A long, narrow excavation dug through overburden, or blasted out of rock, to expose a vein or ore structure.

Wedge - A technique of directing a diamond drill hole in a desired direction away from its current orientation.

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