Black silicon carbide is produced at high temperature in an electric resistance type furnace with quarts sand and petroleum coke as its main raw materials.its hardness is between fused alumina and synthetic diamond. Mechanical intensity of it is hig- her than fused alumina.It is brittle and sharp and has electrical and alumina. It is brittle and sharp and has electrical and heat conductivity in some degree. The abrasives made of it are suit- able for working on cast iron, nonferrous metal, rock, leather, rubber, etc. It is also broadly used as refractory material and metallurgical additive.