Price of product ( USD price or FOB price) : 70 - 115 Product origin : Donghai, Jiangsu, China Key Specifications/Special Features : Superfine: SiO2 99.99% min 1st Grade: SiO2 99.98% min Fe2O3: 0.004% max 2nd Grade: SiO2 99.97% min Fe2O3: 0.008% max 3rd Grade: SiO2 99.99% min Fe2O3: 0.03% max