1 SiO2>99.31% 2 Hardness>8,more than French pebble 3 Our own silica mine&factory 4 Professional manufacturer for 30 years 1. About Silica PebblesName: Silica pebblesOther names: Flint pebbles, Silica grinding pebbles, Silica grinding ballsProperty: Round grayish silica stoneSize: 2-4cm, 4-6cm, 6-8cm, 8-10cm, 10-12cm, 12-15cmApplication: Silica pebbles can be used as a grinding medium for ceramics ...