A very unusual find of high luster Pyrite crystals from the Leonard Mine in Butte, Montana. Few specimens of this sparkly Pyrite still exist intact today, as many of them oxidized heavily from exposure to moisture and weren't neutralized properly. It is effectively a series of exceptionally well formed pyritohedrons that was coated by a generation of druzy Pyrite. 
 
Measurements: 6.60 x 4.60 x 5.00 cm
Ex: Fred Parker Collection.