Exploration and mining terminology

Mineral symbols:

Precious metals Primary ore
Au: Gold Native
Ag: Silver Native
Pt: Platinum Native/Sperrylite
Pd: Palladium Native/Sperrylite
Base Metals Primary ore mineral
Cu: Copper Chalcopyrite
Zn: Zinc Sphalerite
Pb: Lead Galena
Mo: Molybdenum Molybdenite
Fe: Iron Hematite/Magnetite
Ni: Nickel Pentlandite
Sn: Tin Cassiterite

Units/Conversion factors:

Precious metals are typically reported in grams per tonne (metric) or ounce per ton (Imperial).

Base metals are typically reported in percentages of element within a specified amount of the ore.

OPT: ounces per ton
g/t : Grams per tonne



The testing of rocks to determine how much of a particular sought after element is contained within a rock sample. Gold assays look for Au, Copper… Cu, etc.  Precious metals are usually returned as g/t (grams per tonne) which indicates for every tonne of that rock, it should contain the indicated grams of precious metal. Industrial minerals like copper are typically reported as a % of the rock. For every tonne of rock mined, it should contain the indicated percentage of the desired mineral/element.

There are many different types of assays, some are done onsite at operating mines, exploration assays are always done by independent labs with strict protocols for sample handling which must meet NI 43-101 standards.


A horizontal mine working which allows access to the ore body. Also allows for transport and logistics within a mining operation.

g/t Au

Grams per tonne. 1 g/t = 0.03 OPT (ounces per ton). A measure of gold content within an ore. Signifies the average number of grams of gold (Au) contained within one metric tonne of rock.

g/t typically used to indicate precious metal content within an ore.

Indicator Mineral

Minerals in rocks which may indicate a more precious, rarer mineral. Typically sulfides like Pyrite, Pyrrhotite, Chalcopyrite – minerals which rust and leave a orange “rust” stain on rocks.


Ounces per ton. 1 OPT = 34.2818 g/t (g/t = grams per tonne). A measure of gold content within an ore. Signifies the average number of ounces of gold (Au) contained within one imperial ton of rock.

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