Our SiO2 has two categories: crystal granule and cutting pieces The product in this picture is crystal granule. Applied in Cold light coating; Decorative coating; Protective coating We follow critical manufacture standards, quality assurance, welcome your consultation! Specifications Summary: Silicon Dioxide (Chemical formula: SiO2) 1.Crystal granule: 1-3mm; 3-5mm 2.Crystal Pillar: upon demand 3.Color: colorless transparent 4.Purity: 99.99% 5.Package: 1 KG/ bag 6.Storage: avoid exposure to sunlight & acid keep dry Silicon dioxide properties: 1.Cas no.: 7631-86-9 2.Density(g/cm3): 2.2 3.Melting point(â??):1700 4.Refractive index at 550nm: 1.45~1.46 5.Transparency range(μm): 0.2~9 6.Evaporation source: B 7.Application: AR coating; Cold light coating; Filter; Insulating coating; Glasses coating; UV coating