The historic Perth Mint is facing a potential $9 billion recall of gold bars after selling diluted or "doped" bullion to China and then covering it up, according to a leaked internal report.
While the gold remained above broader industry standards, the report estimated up to 100 tonnes of gold sent to Shanghai Gold Exchange (SGE) potentially did not comply with Shanghai's strict purity standards for silver content.
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Doping the gold
Gold doping is a somewhat accepted practice in the industry and is not illegal, but is high risk for refiners, as it lowers the quality of bullion by adding impurities like silver or copper.
Trace amounts of these metals are permitted, but Perth Mint's plan – to keep just within industry standard of 99.99 per cent purity – only left a miniscule margin of error.
The mint began doping its gold as a cost-saving measure in 2018, expecting to save up to $620,000 a year — a tiny fraction of its annual sales.
Within two years this desire to save money would put the mint at the centre of what may be one of the biggest gold scandals in Australian history.