Only small amounts of wurtzite boron nitride and lonsdaleite exist naturally or have been made in the lab so until now no one had realised their superior strength.

 
  • 天然存在或者实验室制造的纤锌矿型氮化硼和朗斯代尔石数量很少,直到现在,也没有一个人发现它们令人吃惊的硬度。
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