Supergene clinobisvanite pseudomorphs after supergene dreyerite from Lively's Mine, Arkaroola, South Australia

Abstract

The Lively's epithermal gold deposit (Arkaroola, South Australia) is located on a dilational splay of the Paralana Fault. Tertiary jasperoids and primary epithermal gold mineralisation of unknown mineralogy were emplaced along the Fault. Eluvial gold and clinobisvanite intergrown with eluvial detritus and Fe oxides indicate that clinobiosvanite is supergene in origin. Tetragonal crystals comprising aggregates of platey clinobisvanite pseudomorph dreyerite. Contrary to suggestions in the literature, the monoclinic BiVO4 polymorph (clinobisvanite) in nature occurs in both high and low temperature settings. At Lively's Mine, the weathering of an epithermal gold deposit that contained minor primary V-mica and bismuth minerals initially formed supergene dreyerite which, with further weathering, later inverted to clinobisvanite.