Miargyrite

This wonderful specimen of the rare silver-antimony sulphosalt Miargyrite is from the San Genaro mine in Castrovirreyna Province, Peru.  It is an incredible specimen formed from thousands of tiny yet well developed Miargyrite crystals of around 1 to 2 mm diameter, forming silvery-black scaley-platelets with a bright metallic lustre.  The specimen is quite remarkable as it is pseudomorphing after some unknown spherical mineral, forming numerous spheres to 1 cm diameter, some of which have open tops forming a hollow, bee-hive like structure.  Amongst the many photographs of Miargyrite from San Genaro on mindat, only one shows this pseudomorphed habit and that is far inferior to this specimen.  These globular aggregates of Miargyrite crystals are piled up over a black granular Miargyrite matrix.  This is a spectacular specimen of this rare sulphosalt, made even rarer by this pseudomorphing habit.