Cyanidation is a chemical process used to recover gold that is very finely distributed in the ore.
When gold occurs in a relatively coarse, free state, it can be recovered by mechanical means such as gravity traps and shaking tables, where the gold separates out because of its high specific gravity. There are various ways to separate and recover gold, depending upon the nature of the ore. Gold is also produced as a by-product of base-metal mines about one-fifth of Canada's gold production comes from this source. It is found as nuggets, flakes or dust in gravel and sand deposits along creeks and rivers, but more often gold is recovered from veins (called lodes) in bedrock. Pyrite, or fool's gold as it is sometimes known, can be distinguished from real gold by its brittleness and hardness as well as the fact that it appears black in powder form.Īs it is the least chemically active of all metals, gold usually occurs in a free or uncombined state. Gold (Au) is a bright, shiny, yellow metal, notable for its high density (19.3 times the weight of an equal volume of water) and valued for its extreme ductility, strong resistance to corrosion, lustrous beauty and scarcity.
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