Siegenite with Chalcopyrite, Galena and Dolomite

Although the Sweetwater mine at Ellington in Missouri, USA, is a lead-zinc producer, it is perhaps most associated with Calcite by mineral collectors.  However, one of its other famously well crystallised species is the cobalt nickel sulphide Siegenite, of which this small cabinet specimen is a really fine example.  Bright, metallic silver octahedral Siegenite crystals to 1 cm feature prominently all over the display face, although their average size is more typically 3 to 4 mm.  These are surrounded by a rich druse of curved translucent white Dolomite crystals, brassy Chalcopyrite crystals and lead grey Galena crystals forming as cubes, cuboctahedrons and foliated cleaved sections.  An outstanding specimen of Siegenite with many other well crystallised species from Sweetwater mine.