Gold Dore Refining :the process, machineries and project ...
2018-1-12 · At most gold mines, the gold "dore" is sent to a refinery for further processing Under rules established by the London Bullion Market Association, LBMA, these bars — the gold standard of the gold world — must be at least 99.5 percent pure gold, weigh between 350 and 430 ounces (most weigh about 400 ounces), and be stamped with a unique ...