Wulfenite

calcite

An unusual columnar structure, possibly pseudomorphous (?), consisting largely of intergrown, colourless-white calcite crystals (to circa 0.2 mm), hosts two thick tabular crystals of transparent pale blue wulfenite, the largest of which measures 5 mm on the diagonal (Exhibit 2). A few larger crystals of white calcite are present on one side of the matrix. The wulfenite crystals are quite gemmy, although both are bruised. They are distinctly blue in colour, but with notable yellow internal reflections and, when lit from certain angles, the yellow colour dominates (Exhibit 3).

The specimen was number 2760 in the collection of Dr Mary L. Johnson. It is accompanied by her handwritten label (Exhibit 4) and an earlier dealer’s label from Minerals Unlimited (Exhibit 5). There is no record of location in the mine.