Magnesium chloride, the English name for magnesium chloride, chemical formula MgCl2, usually with six molecules of crystal water, that MgCl2 · 6H2O, easily deliquescence, placed in dry air, lose crystal water will be weathered. Monoclinic crystal, there are salty, have a certain corrosive. For the metal magnesium, disinfectants, frozen brine, ceramics, and used to fill the fabric, paper and so on. The solution mixed with magnesium oxide, can be a hard wear-resistant magnesia cement.