It is a hard, transparent or translucent crystal largely composed of colorless Sio2 and often contains small amounts of impurities.

 

Quartz is a mineral with very stable physical and chemical properties, and its crystal is an oxide mineral of the tripartite crystal system. Quartz lump, also known as silica, is mainly used as raw material of quartz sand (silica sand), quartz refractories and ferrosilicon.

 

Transparent quartz is called Krystallos by Greeks, meaning pure white ice. They were convinced quartz was durable and hard ice. In ancient China, people believed that cold quartz in the mouth would quench their thirst.