This is a very significant large display specimen of this very rare lead-arsenic sulfide species, from its most important, and type, locality. The piece was found in 1984, and passed through the museum there and a private collector, before being sold by the prestigious Swiss dealership Siber & Siber into the Brent Lockhart Collection. This crystal is a shocking 2.3 cm in length! It may be a little rough at the top (contact and broken in back, but complete from the display face), but the crystal is so big and imposing, that it is of some significance. comes with custom made display base. Joe Budd photos. Ex Brent Lockhart Collection