Tabular Alumina Item Unit Index Typical Chemical composition Al2O3 % 99.00min 99.4 6 SiO2 % 0.20max 0.17 Fe2O3 % 0.10max 0.06 Na2O % 0.40max 0.25 Bulk density g/ cm3 3.50min Absorbing water rate % 1.5max Porosity rate % 5.0max Grain size mm 0-1, 1-3, 3-5 Fine powder mesh - 220, -325