1.high purity & density alumimum oxide 2.competitive price for sapphire growing 3.types: powder, ball, pellet, crackle High purity Alumina pellet 99.998%High purity alumina pellet, the raw material for sapphire crystal growth is fine processed with high purity alumina powder, which is research and development by our company independently. It has the characteristics of high purity, high density, ...