Crednerite

This specimen of Crednerite, a rare copper-manganese oxide, was found in the manganese pods within the limestone at Torr Works quarry (Merehead quarry) at Cranmore in Somerset, England. Often, the sprays of metallic, slightly sooty-black crystals are only a few millimetres across, but this off-matrix specimen has crystals to 2.4 cm across, which are quite exceptional.  Tiny green patches of what is probably Chloroxiphite are sparsely scattered over the Crednerite crystals.  An excellent Crednerite which would sit very comfortably within any SW England or British collection.