Dims: 1.22x0.67x0.71" (3.1x1.7x1.8 cm)
Wt: 0.41 oz. (11.7g)
Langban, Varmland, Sweden
This pyroaurite specimen is from its type locality (Langban). It is perhaps 50% pyroaurite by weight, with most of the rest being calcite and a metal sulfide that I can't identify for certain (it is shiny and almost black, and the only crystal fragment I can see under a loupe looks a lot like magnetite). The pyroaurite is a thick band of an off-white mass of tiny, platy, transparent crystals that have a fairly distinctive reflection pattern under a loupe. The calcite base is noticeably whiter, reflects light differently, and (most distictively) fluoresces a bright orange under short-wave ultraviolet light.