This is one of the biggest, well-formed crystals of Chalcopyrite we've ever seen for sale from any locality, although this famous Mexican location produced some that were even bigger and heavier. It is a LARGE, very bright, very beautiful, complex crystal with sensational brassy yellow-green color and metallic luster. It has well-defined crystal faces and edges and looks to be composed of several, smaller, intergrown, tetrahedral crystals. It is the perfect size for a "big specimen" of the species, without the weight of a large plate, and with the impact of the solid crystals front and center for the mass. The main crystal measures nearly 3 inches on edge and it, along with the other smaller crystals, all display fine-scale stepped growth, triangular patterns on their surface for great geometric aesthetics! The brilliant metallic luster, angular crystals and crystal arrangement make for a well composed piece. The Bolivar Mine is a copper-zinc-silver-gold mine and has produced some fine Chalcopyrite specimens and this piece is one of the best we've seen and it sits nicely on its own for display. Ex. Chester Lemanski collection via Peter Megaw collection in 2007. 1 kilo mass!