Bauxite the main component is alumina, aluminum hydrate contains impurities alumina, is a kind of earthy mineral, white or gray white, because of iron and brown yellow or light red. Extremely difficult to melt, insoluble in water, soluble in sulfuric acid, sodium hydroxide solution. Mainly used in aluminum smelting, refractory system. Advantages: 1. Strong chemical stability and good physical performance 2. Light weight, good thermal stability and high temperature resistance 3. Resistance to mechanical vibration Application: 1. Aluminum industry 2. Precision casting 3. Refractory materials 4. Abrasive materials