chalcopyrite - teaching student specimens from a mineralized vein - Unit of 10 smaller specimens

chalcopyrite   CuFeS2 Mibladen Mining District, Morocco Chalcopyrite is the primary sulfide ore of copper. The brassy yellow color, hardness 3.5-4 and greenish gray streak distinguish it from pyrite, hardness 6-6.5, which is paler, cannot be scratched by a nail and which has a brownish black streak. This chalcopyrite comes from the old galena/fluorite mining district at Aouli, Midelt Province, Morocco. French companies operated mines in the Aouli vein-type lead-zinc deposit from 1923 to 1960, part of a larger lead ore mining area about 16 miles northeast of Midelt in the Middle Atlas Mountains. This area was actively mined until 1975, though local residents occasionally resume small  operations. These specimens are from a mineralized vein and are associated with quartz, some malachite and occasional azurite. As chalcopyrite weathers, it becomes a dull gray-green. If treated with acid it tarnishes to an iridescent blue and purple, making it look like bornite. We prefer that students see