This killer 2.3 x 2.3 x 2.5 cm single black twin is heavy and robust! Unusual, even in a fine thumbnail, this is not only a ferberite but the classic and rare V twin style from a very important find. It is from Brian Kosnar (Mineral Classics, Black Hawk, Colorado) on February 7, 2011, which is notable since Brian had the pocket at the time and the best specimens in general - all of which sold quickly in Tucson 2011. I never saw this - Alex scarfed it up so fast! Photo by Jeff Scovil.