Ferberite

Not that long ago we used to refer to Ferberite as Wolframite, but those less-complex days are long since gone!  Ferberite is the iron end-member of the manganese-iron wolframite solid solution series, the Mn end being Hübnerite.  This delightful large thumbnail has a 1.9 x 0.9 x 0.3 cm black Ferberite bladed crystal, with a bright reflective metallic lustre, standing vertical on a mixed Galena and Pyrite matrix coated in snow-white Calcite crystals.  The Calcites are themselves superb, forming individual, highly distorted and flattened rhombohedrons, which stack to create vermiform (worm-shaped) chains which criss-cross the matrix surface.