... product used high-quality bauxite,coal and other raw material,ceramic sintering,is a natural quartz sand,glass balls,metal ... positive effect. 2.Production Process : Use unique quality bauxite raw material, through a unique grinding, granulation and sintered at high temperature ... psi) and 103 Mpa (15000 psi) 2.Bulk Density : Low Density ; Middle Density and High Density.Cover 0.425-0.85 mm,0.212-0 ...