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人们从古代起就开采银矿。在欧洲,国王们都曾把它视为本国财富的源泉。比如,当西班牙银矿日趋枯竭时,美洲被发现了,西班牙国王欣喜万分,因为这使他获得了墨西哥和秘鲁的巨大银矿。在250 年间,秘鲁波托西银矿每年为西班牙的国王们生产价值400万美元的银子。

在美国加利福尼亚淘金热的年代,人们曾诅咒粘附在金砂上面的“黑土”。后来他们才无意中发现这 黑土 原来是银矿沙!

银是所有金属中分布最广泛的金属之一。有时它以银块的形式存在,在挪威就曾发现过一块重达3/4 吨的银块!但是,通常都必须通过分解矿石才能把银从中提炼出来。
在银矿中,银通常是与硫化合成硫化银,或者成为其他硫化物的一部分,这些硫化物主要是硫化铜、硫化铅或硫化碑。在美国,银大都与铅共生。事实上,银存在于多种化合物中,因此把银从其他元素中分离出来的方法也是多种多样的。
银很软,纯净状态的银无法使用,因此它必须与其他金属化合起来。例如,银币含有90%的银和10%的铜。制造珠宝首 饰和银 器所 用的标准 成 分银中,银占 92.5%,铜占7.5%。
纯银在纯净的空气中不会失去光泽。当它变黑时,就是一个信号,表明空气中含有来自城市烟尘或石油钻井中的硫。除了金之外,银是最易加工的金属。1盎司的银可以拉成30英里长的银丝!银还是电和热的最佳导体。
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