Quartz sand filter media is a hard, wear-resistant, and chemically stable silicate mineral, with its main mineral component being SiO2. The color of quartz sand is milky white with a reddish tint or colorless and translucent. When the SiO2 content is above 98.5%, the Mohs hardness is 7.5; when the SiO2 content is below 98.5%, the Mohs hardness is 7. It is brittle with no cleavage, exhibits a conchoidal fracture, has a greasy luster, and a relative density of 2.65. Its chemical, thermal, and mechanical properties show significant anisotropy. It is insoluble in acids and slightly soluble in KOH solution, with a melting point of 1750°C.