Gamma alumina
Description
A synthetic, tetragonal crystalline form of Aluminum oxide. As an abrasive, gamma alumina removes silver tarnish effectively with few visible scratches (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