常言道,物以稀为贵。人类发现钻石虽已有三千年的历史,但迄今为止,总开采量也才330多吨。钻石又多埋藏在地面以下数百米深的金伯利岩内,以世界上含量最丰富的南非金伯利矿为例,每100吨矿石中也只能找到72克钻石。可见,开采钻石功夫之大实比沙里淘金还难。钻石的稀少,早在中世纪就促使许多人研究与试制钻石的代用品。很早以前就有玻璃工人试制具有较高折射率的玻璃,今天则有更多的人在研制各类耐高 As the saying goes, things are rare. Although diamonds have been found for three thousand years, human beings have so far produced more than 330 tons of total. Diamonds are buried more in the kimberlite hundreds of meters below the ground. Take the South African kimberlite, the richest one in the world, for example, only 72 grams of diamonds are found per 100 tons of ore. Can be seen that the large diamond mining diamonds hard to gold than the sand. The sparseness of diamonds led many to research and prototype diamond substitutes back in the Middle Ages. A long time ago, glass workers try to have a higher refractive index of glass, today there are more people in the development of various types of high