特别广播英语第 33 课：Diamonds 钻石-2

India's supply of diamonds was finally running out after 2,500 years of mining the stones. 因为印度的宝石经过了2500多年的开采，采到最后已经快被采光了。

In the 1800's, two other important areas were found in Russia and South Africa. 到了19世纪，在俄国和南非也发现了两个重要的钻研矿区。

Today, most diamonds used in industry come from Russia. 今天大部分工业用金刚石都产自俄国。

Most diamonds used as gems come from South Africa. 作珍宝装饰用的绝大部分钻石都产自南非。

Only 25 percent of all diamonds mined are good enough for cutting into gems. 在开采出来的钻石总数当中只有25%的钻石，品级够得上可以打磨成珍宝。

Most of the diamonds in India were found in stream beds. 印度的钻石绝大部分是在河床中发现的。

People would pick up handfuls of gravel from the bottom of the streams and sort out the diamonds. 众都是从河床底上捧起一大把一大把的砾石，然后从中挑拣出钻石来。

These diamonds were probably carried from where they were formed to India by great sheets of moving ice that covered parts of the earth 20,000 years ago. 这些钻石很可能在两万年前，整个地球各地都被大片大片的冰川所覆盖着的时期，从钻石生盛典的地方顺着冰川流到印度来的。

Most diamonds today are not found in stream beds, however. They are mined from rock formations deep inside the earth called pipes. 可是，今天绝大多数的钻石都不是在河床上找到的；今天的钻石都是从地球内部很深的地方，从被称为岩筒的管状矿脉的矿井中开采出来的。

Scientists believe that these are parts of volcanoes that were formed when molten rock pushed upward through the earth's crust. 专家们认为这些岩筒都是火山的一部分，是在溶岩从地壳的裂缝中挤压到上面来的时候形成的。

The hand rock in which diamonds are found is called blue ground. 里面含有钻石的坚硬的矿石叫蓝脉矿。