Chalcopyrite
Species
Common · CuFeS₂
The chief copper mineral of porphyry copper deposits and a very common copper ore. Its iridescent surface tarnish results from oxidation producing thin interference films. Despite its golden colour it is brittle, far softer than pyrite, and leaves a greenish black streak.
Identity
- Formula
- CuFeS₂
- Chemical class
- Sulfide
- Also known as
- Copper pyrite, Peacock ore (tarnished iridescent variety)
- Ore of
- Copper
Crystallography
- Crystal system
- Tetragonal
- Habits
- Massive, Wedge-shaped, Botryoidal
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 3.5
- Density
- 4.2 g/cm³
- Luster
- Metallic
- Colors
- brass-yellow, metallic yellow, multicolored
- Streak
- greenish black
- Transparency
- Opaque
Geology
- Origins
- Hydrothermal, Igneous
- Host rocks
- Granite, Volcanic rock
- Associated minerals
- Pyrite, Sphalerite, Galena, Quartz
- Found in
- Hydrothermal vein (lode), Porphyry copper deposit, Skarn, Volcanogenic massive sulfide deposit
- Geography
- worldwide
Classification
- Rarity
- Common
- Gem quality
- No
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Chalcopyrite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Chalcopyrite. Mindat.org (Hudson Institute of Mineralogy).
- D. Barthelmy, Chalcopyrite Mineral Data. Webmineral.com.
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