The bronze MEDALS are largely copper because burnished bronze and gold are similar in color, and the mint did not want any confusion as to which medal an athlete receives.

铜牌主要是铜，因为铮亮的青铜和金在色彩上很相近，再说，铸币厂也不希望在给哪位运动员办法哪枚奖牌的事上产生混乱。

youdao

Great Britain was the first country to adopt the gold standard, when the Mastet of the Mint, Sir Isaac Newton, established a fixed price for gold in 1717.

造币厂厂长以撒牛顿爵士1717年确立了黄金的固定价格，大不列颠是第一个采用本位制的国家。

youdao

This week, the Perth Mint in Australia showed off the world's biggest (and, predictably, the world's most valuable) gold coin.

这周，澳大利亚佩斯铸币厂展示了目前世界上最大的（同时，也是价值最高的）金币。

youdao

The bronze medals are largely copper because burnished bronze and gold are similar in color, and the mint did not want any confusion as to which medal an athlete receives.

VOA: standard.2010.02.16

However, the price of gold and silver changed relatively quickly so that it became pointless to mint gold coins.

FORBES: A Gold Standard Is Big Oil's Best Defense Against Political Attack

U.S. Mint gold bullion coin sales have hit 203, 500 so far in April, the most of any month since December 2009.

FORBES: METALS OUTLOOK: Gold Market To Focus On Central-Bank Meetings, Jobs Report, Physical Demand

He buys gold from the Perth Mint, which actually has the backing of the Australian government.

FORBES: John Mauldin Talks Up Gold