malacolite gneiss

例句：

1. 1.The mineral malacolite is a common rock in the region.
   该地区常见的矿物是黑云母。
2. 2.The geologist found that the malacolite gneiss was formed by the metamorphism of ancient rocks.
   地质学家发现，这种黑云母片麻岩是由古老岩石的变质形成的。
3. 3. The malacolite gneiss has been used as an important building material in many parts of the world.
   这种黑云母片麻岩在世界许多地方被用作重要的建筑材料。