Australia's gold miners may soon have access to a technique to extract gold without the environmental risks associated with cyanide.
Highly toxic cyanide is used in mining to dissolve gold and ores, but the process is often banned in sensitive environments due to contamination concerns.
CSIRO scientists and US gold mining giant Barrick Gold recently collaborated to produce a gold bar without using cyanide for extraction.
The partners last month demonstrated a new process using a chemical called thiosulphate to commercialise gold at Barrick's Goldstrike plant in Nevada.
CSIRO gold processing team leader Paul Breuer said interest in the patented technology was growing.
"There's definitely more interest around but it comes down to the economics," he said.
While studies are yet to be carried out on rehabilitating mines after the process, Mr Breuer predicts the environmental benefits of using a less toxic process will be significant.
"Waste and tailings dams would be quicker to rehabilitate using this process," he said.
However, the use of thiosulphate could be more expensive, and the success of the process depends on the suitability of the ore body.
For decades thiosulphate has been a potential alternative to cyanide but attempts to process the ore have had limited success.
Mr Breuer said there were also potential applications for the recovery of copper, gold, nickel and uranium.
A spokesman for Australia's biggest gold miner, Newcrest Mining, said the company had previously worked with the CSIRO on trials using thiosulphate at its Cadia Valley operations in NSW.
"We did do some work with CSIRO on this recently but we're not doing any more at the moment," a spokesman said.
"We're always exploring alternative processing options."
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