... :2.5-3.2g/cm399.995% series high purity aluminum oxide99.995% High purity alumina gamma powder(D50:40micron) and granulars ... (ball,diameter:0.5-5.0mm) as raw material for sapphire crystal,the quality ... in them ,please contact us for more informations. Appearance: high purity, fine granules, well-distributed particle size, odorless, white powder ...