Brucite is the mineral form of magnesium hydroxide, with the chemical formula Mg(OH)2. It is a common alteration product of periclase in marble; a low-temperature hydrothermal vein mineral in metamorphosed limestones andchlorite schists; and formed during serpentinization of dunites. Brucite is often found in association. magnesium ore - natural brucite pirce Brucite is also called as magnesium hydroxide. The molecular formula is Mg(OH)2, with theoretical values of MgO 69%,H2O 31%. It usually shows white, grey and light greenish yellow in color. Whiteness is 80-85, Moh hardness is 2.5, and the relative density is 2.3-2.6. Brucite is a fibrous magnesium hydroxide rarely at home and abroad. It is white color and easy to split. Nowadays brucite becomes ideal substitute for asbestos due to excellent performance and competitive price.