This is a cluster of pseudomorphs of pyrite after marcasite. The pyrite has replaced the two-membered, bladed type of marcasite twin and so we see elongated, bladed pseudos with and oriented overgrowth of small pyrite crystals. There are sa few crystals missing from the front of the specimnen but, in reality, the photo was taken at too low of an angle. All of the crystals further back are complete and it is a handsome specimen!
