Main Constituents

SiO₂                                        : 40.2%

Al₂O₃                                      : 12.9%

MgO                                       : 24.4%

Fe₂O₃                                      : 5.6%

K₂O                                        : 5.0%

CaO.                                       : 1.5%

TiO₂                                        : 1.4%

Na₂O                                      : 2.0%

Cr₂O₃                                      : 0.3%

Loss on ignition                                 : 5.9%

Others                                    : 0.8%