... -74um,120-800mesh 3.ISO 9001-2000we are specifically in supplying alumina powder,99.0% -99.8%,0.3-74um,120-800mesh ... very much for your attation.This product is featured with white powder, loose massive, easy tocrush, stabilityin the high temperature, not dissolve ... -1,Al2O3 >=99.7%325mesh good active character,suitalbe use in super refractory materials.do polishingNa20 <=0.1%500mesh SiO2 <=0 ...