Metals that are found in the form of elements in nature can be extracted by using physical methods.For example,we can separate the denser gold grains form small pieces of rock by panning.

 
  • 本质上以元素的形式被找到的金属能被使用物理的方法提龋例如,我们能通过平绒分开较稠密的黄金粒形式小的块的岩石。
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