hingganite

例句：

1. 1.The mine is producing a hard rock mineral that is in high demand.
   这个矿正在生产一种需求量大的硬岩石矿物。
2. 2. The mining company has been extracting this hard rock for decades.
   这家矿业公司几十年来一直在开采这种硬岩石。
3. 3.The hard rock formations are visible from the surface of the mountain.
   从山顶上可以看到这些硬岩石的形成。