The nature of quartz sand structure and classification

Quartz sand is a hard, wear-resistant, chemical stability of silicate minerals, the main mineral component is SiO2, quartz sand color is white or colorless, translucent, hardness 7, brittle no cleavage, conchoidal fracture, oil sheen, the relative density of 2.65, its chemical, thermal and mechanical properties have obvious anisotropy, acid-insoluble, slightly soluble in KOH solution, melting point 1750 ℃.
Quartz can be classified according to the quality of ordinary quartz sand, fine quartz sand, high purity quartz sand, fused silica sand.
1, ordinary quartz sand:
SiO2 ≥ 90-99% Fe2O2 ≤ 0.06-0.02%, refractoriness 1750 --- 1800 ℃, the appearance of some large particles, the surface of yellow cysts. Particle size range 5-220 mesh, users can request granularity production. Main purpose: metallurgy, ink silicon carbide, glass and glass products, ceramic, steel, water filtration, sodium silicate, chemical, jet noise and other industries.
2, refined quartz sand:
SiO2 ≥ 99-99.5% Fe2O3 ≤ 0.02-0.015%, selected high-quality ore complex processing. With 5-480 mesh size range, according to user requirements, the appearance of a white or crystalline. Main purpose: High quality glass, glass, refractories, smelting stone, precision casting, grinding wheel and other materials.
3, high purity quartz sand:
SiO2 ≥ 99.5-99.9% Fe2O2 ≤ 0.005%, is the use of 1-3 grade natural crystal stones and high quality natural stone, carefully selected, fine processing. Particle size range of 1-0.5mm, 0.5-0.1mm, 0.1-0.01mm, 0.01-0.005mm, according to user requirements.
4, fused quartz sand
Chemical composition: SiO2 99.9-99.99% Fe2O3 10PPM-25PPM maxLi2O 1-2PPM maxAl2O3 20-30PPM maxK2O 20-25PPM maxNa2O 10-20PPM max Physical Properties: colorless transparent block, granules or white powder. True specific gravity: 2.21; Mohs hardness: 7.0; PH value: 6.0.