Magnesium oxide(MgO)content % ≥ 42

Calcium oxide(CaO) % ≤ 0.04

Content of acid insoluble % ≤ 0.01

Iron(Fe) % ≤ 0.001

Chloride(Cl) % ≤0.01

Water % ≤ 5.0

Apparent specific volume(ml/g): 0.10