Product specification: SiO2 Min.99% A1203 Max. 0.5% Fe203 Max. 100 ppm (0.01%) CaO Max. 0.5% MgO Max. 0.5% TiO2 Max. 0.05% NaC1 Max. 500 ppm Cr203 Max. 5 ppm Size (1) Less than 900µm: 0% (2) 710 µm 900 µm: Max. 1% (3) 600 µm 710 µm: Max. 5% (4) Bigger than 106 µm: Max. 8%