This old museum specimen dates back to the late 1800s - large ones are very rare! The unique triangular shape has been created by three intersecting crystals. The lustrous, battleship gray, crystals appear to be doubly terminated. The longest crystal exhibits the sectile nature of this species with a nice bend, two thirds down from termination. Fewer of these great old classics are seen each year. This is a really elegant specimen for its overall form, I think! It was deaccesssioned from the Carnegie Museum in the first or second annual Carnegie Auction in the mid-1990s