Willemite (w. conichalcite, quartz and rosasite)

calcite; conichalcite; olivenite (?); quartz; rosasite

A dark, dense matrix of extensively oxidised sulphide ore in which acicular crystals of olivenite (?) and transparent, yellow-green crystals of willemite (?) are discernible. More prominent, however, is the bluish-green crust covering much of the specimen and labelled as "serpierite" by previous owners. XRD analysis of this crust (Paul Carr; University of Wollongong, 2023) showed it to be an intimate intimate intergrowth of willemite and rosasite, with minor conichalcite and quartz.

Mark Feinglos purchased the specimen from Julius Zweibel in February 1990. There is no record of its location in the mine.