Moreover, the processing of ores introduced poorly controlled changes in the concentrations of minor and trace elements in the resulting metal.

此外，对矿石的加工过程也在随之而形成的金属中引入了某些有失控制的次要和微量元素含量的变化。

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Mainly coarse grained gold, along with pyrite, pyrrhotite, arsenopyrite, and minor base metal sulfides, occur in networks of quartz veinlets, brecciated wallrock, and disseminated in altered wallrock.

大部分粗粒金主要赋存在网格状石英细脉和角砾状围岩中的黄铁矿、磁黄铁矿、毒砂和少量贱金属硫化物中和以分散状分布在蚀变围岩中。

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Secondly, we deliberately mine, or do not mine, certain deposits of those other minerals as a result of the co-production of indium (this same economics is true of all of the minor metals, indeed, the definition often used of minor metal is one that is extracted as a co-product).

FORBES: What Will Apple Do When Indium Runs Out in 2017?

So the correct paint has been applied to those areas that have suffered corrosion, and a bolt with the right kind of metal has been attached to a fitting that earlier caused the "minor" flood.

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