Doré 

Unrefined gold and silver bullion bars usually consisting of approximately 
90% precious metals that will be further refined to almost pure metal.

Drift

A horizontal passageway in an underground mine that follows a vein of ore 
or rock formation.

Dump

The site for disposal of waste rock from the mine that may be extremely 
low grade.

EIS

Environmental impact study.

Flotation 

The process of mixing powdered ore with water and chemical reagents to 
separate the metallic particles from the waste rock; the metallic particles are 
collected and dried and this concentrate is sent to the smelter for refining.

Gangue

The undesired materials or valueless mineral particles associated with ore 
that must be rejected or discarded.

Geophysical 
survey

A method of prospecting that measures and maps the physical properties 
of rock formations by analyzing magnetic anomalies, assessing rock density 
with gravity surveys, and measuring electrical conductivity anomalies and 
radioactivity.

Grade

The amount of metal in each ton or tonne of ore, expressed as troy ounces 
per ton or grams per tonne for precious metals and as a percentage for 
other metals. A term such as cut-off grade refers to the minimum metal 
grade at which an ore body can be economically mined.

Grizzly

A steel grate or mesh placed over a chute that restricts the size of ore or 
rock that passes through.

Head grade

The average grade of ore fed into a mill.

Heap leaching

The process of extracting valuable metals (usually gold and silver) from 
crushed ore by applying leaching solutions, which percolate through the 
stacked ore (or heap) and are collected by a sloping, impermeable liner 
below the heap.

Indicated Mineral 
Resource*

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 testing 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.

Industrial mineralsNon-metallic minerals used in the chemical and manufacturing industries.

Inferred Mineral 
Resource*

That part of a Mineral Resource for which quantity and grade or quality can 
be estimated on the basis of geological evidence and limited sampling and 
reasonably assumed, but not verified, geological and grade continuity. The 
estimate is based on limited information and sampling gathered through 
appropriate techniques from locations such as outcrops, trenches, pits, 
workings and drill holes.

© 2013 KPMG LLP, a Canadian limited liability partnership and a member firm of the KPMG network of independent member firms 
affiliated with KPMG International Cooperative (“KPMG International”), a Swiss entity. All rights reserved.

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 A Guide to Canadian Mining Taxation