This is a lustrous, major crystal of a very rare species from Butte or anywhere, here at a world class level. This is a monster for the size and has superb form as well. It is complete all around. Ex. American Museum of Natural History, with modern label present, exchanged to Larry Conklin some 20 years ago and since in his private rarities/miniatures collection. Courtesy of Montana dealer and collector Chris Tucker: Your pearceite, BEM-62 really looks like Neihart material! I assume that the white material is Baryte, and if so, is very common for Neihart. Similar pieces came from the Queen of the Hills, Moulton, Florence, Big Seven, and Galt mines all at Neihart. (In the late 1800s, Lazard) Cahn handled a bunch of material from Neihart and I wouldn't be surprised if it came from him as well.