Cyclone Manufacturing 5021 Aluminum Oxide Abrasive Media, 60 Grit (50 lb. Box). Widely used as a cutting media. It can produce an anchor pattern in preparation for re-coating. It is excellent for removing heavy foreign matter, deburring, etching glass, and lettering stone. It is extremely fast cutting, and can be reused several times before discarding. This is a silica-free abrasive. Exposure to silica is known to causes severe and often fatal damage to lung tissue. DO NOT ever use silica sand in abrasive blast equipment.