... of metal, stone and glass;(3)Filter medium of chemical industry, petroleum, pharmacy and water treatment; (4)Grinding of marble, ... glassware, leather and other materials;(5)Raw material of grinding wheel, oil stone, emery cloth and abrasive paper; (6)Wear-resistant material ... of ancient buildings, metal, glass and ceramic fine polishing, grinding Do fine sandblasting, mainly used in the surface being ...