172copper occurs in nature mixed with other minerals and valuable metals in ore, and the proportion of copper in the ore can vary considerably.

172铜在自然中与其他矿物和有价值的金属混合存在于矿石中，而且矿石中铜的比例可能有很大差别。

youdao

Chinese mining and metals firms have been scouring the world for promising reserves of iron, copper, bauxite and other key industrial minerals.

中国采矿和金属企业也在全世界寻找有潜力的铁、铜、铝和其它关键工业矿产资源。

youdao

Copper occurs in nature mixed with other minerals and valuable metals in ore, and the proportion of copper in the ore can vary considerably.

铜在自然中与其他矿物和有价值的金属混合存在于矿石中，而且矿石中铜的比例可能有很大差别。

youdao

The company is engaged in exploration for, and mining and sale of coal, copper and other minerals.

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Exxon Mobil is engaged in exploration for, and mining and sale of coal, copper and other minerals.

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Exports of coal, copper and other minerals from Utah, Wyoming and Montana are beginning to slip because of falling demand in Asia and cut-price competition from Russia and China.

ECONOMIST: The West