The mining industry represents a large part of the economy in Canada. Ontario is the largest producer of gold in the nation, producing 53% of Canada's total minerals production in 2007 [1]. Despite its high toxicity, cyanide is commonly employed in the extraction of gold from its ore. Its use represents an environmental hazard due […]

The evermore increasing complexity of gold ores is forcing operations to seek alternative gold leaching reagents to the traditional use of cyanidation. At the Barrick Goldstrike mine, the implementation of a non-toxic thiosulfate leaching process is about to become an industrial reality. With modification to the existing infrastructure and leaching circuit, this new process allows […]

Autoclave treatment of refractory sulfide gold ores oxidizes minerals, such as pyrite, containing gold that cannot be recovered through conventional cyanidation. Oxidation liberates the gold by putting iron into solution. At high temperature and pressure, the dissolved iron tends to precipitate. A problematic iron precipitate that may form is basic iron sulfate (BFS). In the […]

Gold occurs in association with pyrite and arsenopyrite in the Carlin-type gold deposit, with little gold being contained in carbonaceous materials. Extracting this gold requires pretreatment, such as pressure oxidation or roasting, to remove carbonaceous materials and sulphides, followed by the application of alkali cyanide or thiosulphate solution to leach gold. These processes are energy-intensive […]