This very dense specimen of silver sulphosalts from Freiberg in Saxony has the feel of something of significant age and looks more complex than the Stephanite and Acanthite listed on its label. The matrix comprises a thin bed of lenticular to platy Siderite crystals, beige in internal colour, but greyish-white upon their surface. Upon one side (the display surface) a ridge of dark grey silver-bearing species rises, but amongst these is a variety of forms. Firstly, several quite large (the largest to 1.1 cm across) rounded dark purple-grey crystals with a resinous lustre, and reminiscent of Pyrargyrite, sit upon the Siderite and stacked upon each other. Oddly, this species also appears to show well-developed cubic cleavage and it is unclear if these cubic surfaces have been interpreted as Acanthite crystals. Then, there are less well-defined smaller steely-grey crystals which might well be Stephanite. Either way, a fascinating, and very rich old-time silver sulphosalt specimen. Ex Hans Engelbrecht Collection, no. 2999.
