Alpha alumina
Description
The synthetic, hexagonal crystalline form of Aluminum oxide that occurs naturally as the mineral Corundum. As an abrasive, alpha alumina removes silver tarnish effectively but also removes a significant amount of silver (Wharton, et al, 1990).
Additional Information
° G.Wharton, S.Lansing, W.Ginell, "A Comparative Study of Silver Cleaning Abrasives" JAIC 29:13-31, 1990. LINK