A very old and very fine Tri-state classic! Ex collection of the Arizona-Sonora Desert Museum, This is a true top shelf specimen. Sphalerites here reach to 4 CM and are exceptionally well-formed. The smaller crystals are a fine ruby red (ruby-jack) while the larger ones are darker and coated with Chalcopyrite. Some faces are noticeably iridescent and over all the luster is outstanding. The only damage is at the outer edges where it would be expected, the display face is pristine, three dimensional and very esthetic. The old Tri-state area produced a lot of materials in its time, but this quality was excellent even in its heyday.