There exist two primary types of glass derived from high-purity fused silica (SiO2). The first is transparent quartz glass, which is produced using crystalline quartz as its raw material. The second is opaque silica glass, also known as silicate glass, which is manufactured from fused quartz as its source material.
Quartz is typically transparent, but opaque quartz can exhibit a milky or cloudy appearance due to internal air layers (bubbles) or the effects of processing.
Owing to its high purity, chemical resistance, optical properties, heat resistance, and electrical insulation qualities, quartz is widely used across various fields.