Also known as silica, Quartz, Quartz stone) is a texture hard, wearresisting, stable chemical properties of silie minerals, in nature exist in Quartz sandstone, quartzite and vein Quartz. 1, ordinary quartz sand; SiO2 9099% Fe2O3 or less % or higher, refractoriness 1750 amp;#8451;, the exterior part of the larger particles, the surface has a yellow skin cyst. 3, high purity ...