Bornite
Species
Common · Cu₅FeS₄
Peacock ore: copper red to bronze on a fresh break, it soon tarnishes to iridescent blues and purples. With about 63 per cent copper it is an important ore beside chalcopyrite in porphyry copper deposits, and occurs too in skarns, pegmatites, mafic rocks and copper-bearing shales. Named for the Austrian mineralogist Ignaz von Born.
Identity
- Formula
- Cu₅FeS₄
- Chemical class
- Sulfide
- Also known as
- Peacock ore, Peacock copper, Variegated copper ore
- Ore of
- Copper
Crystallography
- Crystal system
- Orthorhombic
- Habits
- Massive, Granular, Cubic, Dodecahedral
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 3
- Density
- 5.07 g/cm³
- Luster
- Metallic
- Colors
- bronze, reddish brown, purple, blue
- Streak
- pale grayish black
- Transparency
- Opaque
Geology
- Origins
- Hydrothermal, Igneous, Metamorphic, Sedimentary
- Host rocks
- Granite, Volcanic rock, Marble, Sandstone, shale and clay
- Associated minerals
- Chalcopyrite, Pyrite, Chalcocite, Covellite, Grossular, Calcite, Wollastonite, Quartz
- Found in
- Pegmatite deposit, Porphyry copper deposit, Skarn
- Geography
- USA (Butte, Montana; Bisbee, Arizona; Kennicott, Alaska), England (Cornwall), Kazakhstan (Dzhezkazgan), South Africa (Okiep), Australia (Mount Lyell, Olympic Dam), Zimbabwe (Mangula)
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, Bornite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
- Bornite. Wikipedia.
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