A very rich and showy silver ore specimen from the San Luis Shaft at Fresnillo, Mexico and the Brent Lockhart Collection. Scintillating, metallic-gray pyrargyrite crystals with spots of gemmy, "ruby-silver" fire comprise nearly the entire piece, which is nicely accented with golden chalcopyrite crystals. A rich bonus on the back are the lustrous, pastel-pink, manganoan calcite scalenohedrons and nail-head crystals (second photo) .