Specific gravity 1.2-1.6g/cm3 hydrochloric acid capacity 2.6%Bulk density 0.36-0.8g/cm3 SiO2 65%Wear rate 1.6-1.8% Al2O3 18-20%Pore clearance 58% Fe2O3 6-8%Specific surface area 3900m2/m3 rare earth element 1.2%