It is melting made of various kinds of pure natural quartz (such as crystal, quartz sand...etc.). The linear expansion coefficient is very small, which is 1/10~1/20 of ordinary glass. It has good thermal shock resistance. Its heat resistance is very high, the frequent use temperature is 1100℃~ 1200℃, and the short-term use temperature can reach 1400℃.Quartz glass is mainly used in laboratory equipment and refining equipment for special high-purity products.