Aluminum oxide Brown aluminum oxide is electrically fused in an arc furnace from a mixture of bauxite at high temperature. It has brown colour, high hardness and great toughness. The abrasives tools made of brown aluminum oxide are suitable for steel, malleable cast iron and hard bronze. It used for refractory aluminum oxide lining mixture, pouring materials castable, etc. White aluminum oxide has white color and a little higher hardness and toughness comparing with the brown one. The grinding tools made of this material are suitable for fine grinding of high carbon steel, high-speed steel and stainless steel, abrasive powder of finer grit size can also be used for precision casting and high-grade refractory. In bags, pallet etc