Black aluminum oxidde abrsasives is a new type abrasive material for polishing various metal works.It is electrical fused in an arc furnace from aluminum oxide as raw material.Black aluminum oxide abrasive is featured with high hardness.strong tanacity,good self-sharpening,better cohesiseness,higher durability,less heat generated in grinding and giving the metal works high finish,less power weakened in grinding.It is mostly used in grinding and polishing stainless steel,metal works,optical glass,bamboo or articles.and it is also the new grinding material of producing colophony grinding wheels, slice,and emery cloth.