Description
This is a fine plate of bournonite “cogwheel” twins, featuring well-defined crystals. The steel-grey crystals have a silky-metallic lustre and in places, there is a patina-like appearance. The specimen is in very good condition – minor chipping and incomplete crystals around the periphery. Mounted for display (as shown in the first photograph), this specimen looks great in the cabinet – really nice!
Most surfaces on the underside/back of this specimen are not fresh, with minor crystallization textures visible with magnification, and other mineralization present (including microscopic pyrite crystals), indicating that the specimen detached from the host rock sometime late in the crystallization sequence at the deposit.