Rock tumbling, Lortone, silicon carbide and aluminum oxide, white and grey, coarse / fine / pre-polish / polish compound. Sold per 4-piece set. - Fire Mountain Gems and Beads
Made in USA - Square Polishing Stone: Aluminum Oxide, 6" OAL - 05942909 - MSC Industrial Supply
Rock Tumbling Grit – Two Pack Step #4, Polish 1200 Fine Aluminum Oxide | Polly Plastics