CHALCOPYRITE, SPHALERITE, PYRITE, QUARTZ, CALCITE (large cabinet)

Sphalerite, a sulfide mineral represented by the chemical formula (Zn, Fe)S, serves as the principal ore for zinc extraction. This mineral occurs in various types of deposits, predominantly within sedimentary exhalative, Mississippi-Valley type, and volcanogenic massive sulfide formations. It is commonly associated with other minerals such as galena, chalcopyrite, pyrite, as well as calcite, dolomite, quartz, rhodochrosite, and fluorite.

Chalcopyrite is a copper iron sulfide mineral and the most abundant copper ore mineral. It possesses the chemical formula CuFeS2 and crystallizes in the tetragonal system. Its appearance ranges from brassy to golden yellow, with a hardness rating of 3.5 to 4 on the Mohs scale. The streak of chalcopyrite is diagnostic, displaying a-tinged black color.

Upon exposure to air, chalcopyrite undergoes tarnishing, resulting in various oxides, hydroxides, and sulfates. Associated copper minerals include the sulfides bornite (Cu5FeS4), chalcocite (Cu2S), covellite (CuS), and digenite (Cu9S5); carbonates such as malachite and azurite; and, less frequently, oxides like cuprite (Cu2O). It is seldom found in association with native copper. Chalcopyrite also serves as a conductor of electricity.

Private Peruvian Collection. Very rare as the mines closed decades ago. Former Steve Moon Collection.