Garnet is also named as corundum or natural corundum. It is very hard and acid resisting and alkali resisting. A kind of aluminosilicate, it has various colors. Recently, it has a variety of red, grey, green, white and so on. So it is a new developed wall painting, and the only colorful shell sand blast abrasive, because of its large quantity of moleculars, so its chemical characteristic is very steady. In short, it is also used as a new abrasive water treatment filter. Physical and Chemical indexes Analysis item Index Analysis itme Index hardness 7.5-8.0% SiO2 38-40 % melting point 1338-1450 ℃ CaO 8.5 % specific gravity 3.7-4.5 g/cm3 MgO 5-6 % acid resistance 98.81% FeO 18-20 % alkali resistance 98.62% AL2O3 20-23 % TiO2 1.0-1.5 % Fe2O3 4.5 %