A relatively rare blue,violet - blue,or greenish - blue translucent mineral,Na4 - 5Al3Si3O12S,the chief component of lapis lazuli.

• 天青石一种比较珍贵的透明矿物质，多呈蓝色、蓝紫色或蓝绿色，Na4－5Al3Si3O12S，是杂青金石的主要成分