ceramics materials mainly composed of spinel. Represented by MgAl2O4 and spinel, the stoichiometric composition is (mass fraction) magnesium oxide 28 3%, 71.7% alumina. Its color is generally colorless, light red, light green and sky blue, its Mohs hardness is 8, its density is 3.58g/cm3, its refractive index is 1.715, and its melting point is 2135 ° C.
No classification at present.