Shocking iridescent patina makes this thumbnail stand out in a crowd of mono-colored examples of this species! This is an extremely aesthetic cluster of equant, short prismatic, lustrous and deep red pyrargyrite crystals, to 9 mm across. Some of the crystals exhibit a light coating of dark gray chalcocite (ID is on museum label). When strongly backlit, it glows a soft translucent red, though this takes strong light. A truly fine thumbnail specimen! Ex. Ben de Wit collection, and the Museum Ootmarsum, Netherlands.