GEMSTONE is a multinational group company dedicated to technical research and production of advanced materials. We have 4 manufacture bases in mainland of China and a wide variety of alumina products are developed such as microcrystal grinding medias(balls and linings), high purity alumina packings, ceramic comb items, etc. Our alumina products stand out in service because of high crush strength, high hardness, premium performance in wear resistance and erosion control. It is worth mentioning that years of marketing witness aggressive development of our TNALU alumina balls and lining bricks series in not only China but also overseas markets. The remarkable performance in energy saving conv ... more