Black corundum

Black corundum dabara adaba maka nhazi nchara, ejiri ya mee ka ájá ájá enyo enyo, ngwaike na-arụ ụlọ ụlọ. N'etiti abrasives nkịtị, ike nke corundum aja aja dị ntakịrị ala. Otú ọ dị, n'ime usoro egweri, ọrụ mgbochi nke mkpụrụ osisi abrasive ya dị mma, nke kwesịrị ekwesị maka ịkwanye ọla ndị nwere ike dị elu, dị ka ihe siri ike na-egweri nke ígwè nkịtị, karịsịa nke kwesịrị ekwesị maka carbon ígwè, nchara nchara n'ozuzu, nakwa maka ịkwanye ígwè a na-esi ísì ụtọ na bronze siri ike.