Black fused alumina is also known as low aluminum corundum. It is also a new type of product on the based of producing brown fused alumina by Ruishi Company. And it is a dark gray crystal body made α- Al2O3 and ferropicotite as main ore in the electric arc furnace by smelting the bauxite.

Black fused alumina is characterized by low Al2O3 and a certain amount of Fe2O3 (10% more or less) content, so it has characteristics of moderate hardness, high toughness, high temperature resistance, and stable thermal stability. It is mainly suitable for free grinding, such as coarse grinding before electroplating products, mainly for polishing and sandblasting of stainless steel, fabricated metal products, optical glass, bamboo products, and it is also new abrasive for manufacturing resin grinding wheels, cut-off wheels and emery cloth. The black fused alumina of the company concentrated basic tablets, with the characteristics of strong cutting power, high toughness, high flexibility, good abrasion resistance and high working efficiency, which is the best product for grinding and polishing, sandblasting stainless steel products.