SiO2≥99.5—99.9％ Fe2O2≤0.005％，It is made of 1-3 grade natural crystal stone and high-quality natural stone after careful selection and fine processing. Granularity range 1-0.5mm, 0.5-0.1mm, 0.1-0.01mm, 0.01-0.005mm, can be produced according to user requirements. Main uses: advanced glass, electronic fillers, smelting stones, precision casting, chemicals, ceramics, etc.