mineral
Chalcopyrite
Copper iron sulfide (CuFeS2)
Hardness of 3.5 to 4 on the Mohs scale, brass-yellow to golden-yellow color often with a distinctive iridescent tarnish (peacock ore), metallic luster, tetragonal crystal system, poor cleavage, specific gravity of 4.1 to 4.3.
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Physical properties
Hardness of 3.5 to 4 on the Mohs scale, brass-yellow to golden-yellow color often with a distinctive iridescent tarnish (peacock ore), metallic luster, tetragonal crystal system, poor cleavage, specific gravity of 4.1 to 4.3.
Formation & geological history
Forms in hydrothermal vein deposits, pegmatites, and sedimentary rocks, often associated with other copper and sulfide minerals.
Uses & applications
Primary ore of copper, used in electrical wiring, plumbing, alloys, and valued by mineral collectors.
Geological facts
Often referred to as 'fool's gold' due to its brassy metallic appearance, though it is softer and darker than pyrite and can be easily distinguished by its greenish-black streak.
Field identification & locations
Found worldwide in copper-bearing ore bodies and hydrothermal veins; identify by its metallic luster, golden-yellow color, and often characteristic multicolored tarnish.
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