The standard for gold purity is 99.999 per cent.
The scandal was originally reported on the ABC’s Four Corners.
Speaking at a press conference this afternoon, Perth Mint CEO Jason Waters said the amount of silver added to the gold sold to China brought its purity from 99.996 per cent to 99.992 per cent.
“These sort of issues are bad for our reputation. It hurts,” he said.
“I want to see that repaired and get back to the reputation that we should have.”
Waters said the gold doping took place before he was CEO.
He said he had spoken with WA Mines Minister Bill Johnston about the incident.
Waters did not go into detail about their conversations.
“Since my appointment last year and since I became aware of it, I had some conversations with the minister about it
“It’s a fresh team here at the mint now.”
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He said gold was now being minted to Shanghai Gold Exchange standards.
Though the doping scandal only became public knowledge yesterday, there was a possibility that the mint would have to buy back 100 tonnes of bullion.
As the mint is wholly owned by the WA government, such a recall would have forced Western Australian taxpayers to pay for the gold.
Waters declined to comment.