Mineralogical note : waylandite from Elsmore, New South Wales

Waylandite, ideal end-member stoichiometry BiAl3(PO4)2(OH)6, is a member of the crandallite group and the alunite super-group. It is a rare secondary mineral, formed by alteration of primary Bi phases, that has nevertheless been reported from eighteen localities worldwide (www.mindat.org). Recently, one of the authors (JR) recovered a specimen from the Elsmore deposit, Elsmore, New South Wales, that proved to be waylandite, with only partial substitution of Al by Fe (end-member BiFe3(PO4 ) 2(OH) 6 is the species zairite). This find represents the first Australian locality for waylandite. While the Elsmore deposit is well known for superb specimens of cassiterite, more recent studies have drawn attention to the presence of an array of rare secondary bistmuth minerals, including koechlinite, rooseveltite and russellite (Rankin et al., 2002). The specimen containing waylandite consists of quartz-rich greisen. Granular, cream to brown material lines a vugh, and appears to be in part replacing an earlier fibrous mineral, probably bismuthinite.