AM_9Al2O32B2O3 Formula: B1.1 Al4.9 O9 Name: 9Al2O3.2B2O3 Unit cell: 7.6942 15.011 5.6689 90.0 90.0 90.0 , V=654.74 Space group: A21AM (36)

Garsche M , Tillmanns E , Almen H , Schneider H , Kupcik V , European Journal of Mineralogy , 3 (1991) p.793-808, Incorporation of chromium into aluminium borate, 9Al2O3.2B2O3 (A9B2), Sample: Rietveld refinement of AgB2