Industrial Grade Garnet Gemstone is derived from hard rock deposits and used as a filtration medium and to provide blast cleaning to a water jet abrasive. Garnet Gemstone is inert, non-toxic and environmentally friendly. Garnet Gemstone is chemically stable and does not contaminate the surface of stainless steel and non-ferrous materials burring the blast cleaning process. Industrial Grade Garnet Gemstone has a specific gravity of 4 and hardness of 8.