Arsenobismite discredited

Reinvestigation of arsenobismite, previously assumed to be a bismuth arsenate with the uncertain formula similar to Bi-2(AsO4)(OH)(3), has demonstrated that it is not a Valid species. The formal discreditation of arsenobismite has been approved by the Commission on New Minerals and Mineral Names, I.M.A. Careful analysis of the type specimen has shown that "arsenobismite" is in fact an intimate association of preisingerite, minor atelestite and minor beudantite/segnitite. Analyses of several other reported arsenobismites, including additional samples from the type locality, and samples from some other world-wide occurrences showed that almost all of these are single-phase beudantite/segnitite.