Magnesite is the general name of minerals with high magnesium content. For example, brucite is a rare high magnesium mineral, also known as "magnesium hydroxide". It is chemically composed of Mg (OH) 2, the theoretical content of MgO is 69%, and the content of metallic magnesium is 41.6%. It is a high-quality magnesium smelting ore Periclase (mainly composed of MgO) made of brucite after roasting is a high-grade refractory