Barrick Gold has pioneered a way to produce gold without having to depend on cyanide’s chemical ability to separate the precious metal from ore.
As much as 60% of the planet’s gold is currently produced using cyanide, a 120-year-old practice that carries environmental risks of groundwater contamination.
The new technique, used by Barrick to get gold from cyanide-resistant ore at its Goldstrike mine in Nevada, will let the world’s largest producer recover about 2.25 million ounces of gold worth $2.6 billion over five years. The technology could also spur other companies to consider new ways to limit the use of cyanide in mining.
“Now there’s a plant up and running it takes away some of the risk,” said Paul Breuer, a Perth-based principal research scientist at Australia’s Commonwealth Scientific and Industrial Research Organization, which worked with Barrick on the process. “People will be very seriously looking at it.”
Barrick and the CSIRO developed a way to use non-toxic thiosulfate to process so-called double refractory ore. The research group has also worked with companies including Newcrest Mining Ltd., Australia’s biggest producer, on techniques to limit cyanide use.
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