Among all commodities, nickel and copper are under particular stress.

在所有大宗商品中，镍和铜尤其承压。

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In May prices for copper, nickel and other metals rose to record levels, although they have since fallen a bit.

5月，铜、镍和其它金属价格升至创纪录新高，尽管此前曾有小幅度下跌。

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The company's output of iron ore, as well as copper, zinc and nickel, surged in the last three months of 2009 because of strong demand from Chinese carmakers and construction companies.

VOA: standard.2010.01.21

Many French horns, for example, are made of nickel silver, an alloy of copper, zinc, and nickel (it's silver in name and color only), and some are made of nickel bronze, an alloy of copper, tin, and nickel. (Brass itself is an alloy of copper and zinc.) Many brass instruments are silver-plated (sterling silver on brass), and some are gold-plated.

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Other commodities like gold, silver, copper, nickel, all are in high demand, and therefore really expensive.

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Jinchuan plans to start using BioHeap in both copper and nickel mines in the next few months.

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