black silicon carbide is produced at hight temperature in an electric resistancetype furnace with quarts sand and petroleum coke as its main raw materials. its hardness is between fused alumina and synathetic diamond. mechanical intensity of it is hig-her than fused alumina.it is brittle and sharp and has electrical and heat conductivity in some degree. the abrasives made of it are suitable for working on cast iron,non-ferrous metal,rock,leather,rubber,etc. it is also broadly used as refractory material and metallurgical additive.special spec. can be supplied on your request.