... , medium bulk density silicon carbide abrasive grain. Description:The high density black silicon carbide fused by heating high purity silicon sand and carbon in ... Fe2O3 0..33%Physical Properties:Color BlackShape AngularCrystal Form Alpha silicon carbide in hexagonal systemSpecific Gravity 3.21Hardness 2750 kg/mm, ... 280, 320, 360, 400, 500, 600, 800, 1000, 1200. Black Silicon Carbide used for Ceramic