Bornite - Encyclopedia

    Class : Sulfides and sulfosalts
    Subclass : Sulfides
    Crystal System : Orthorhombic
    Chemistry : Cu5FeS4
    Rarity : Common

Primary bornite is present associated with basic rocks, high temperature hydrothermal veins and skarn-type metasomatic deposits. Secondary bornite exists as an alteration product in the cementation zone of many copper deposits, where it may be the dominant copper mineral. It was named in honor of the Austrian mineralogist and paleontologist Ignatius von Born. It usually occurs in compact masses, sometimes grainy. It has a metallic luster, a brilliant bronze to pinkish-brown color on fresh exposure, rapidly dulling to red, copper-red, blue-purple or purplish with pronounced iridescence. Pseudoquadratic crystals of cubic, octahedral or dodecahedral appearance with striated curved faces, remain very rare, generally of millimeter size, although individuals of 8 cm are known. Bornite is one of the most important copper ores.

Bornite in the World

The best crystals come from the mines of Cornwall, where superb stalactites of imbricated centimetric crystals have been discovered (Redruth, Camborne), and from Mangula (Bulawato, Zimbabwe), which delivered 50 mm bronze trapezohedra. Beautiful samples also come from Butte (Montana), Prägraten (Austria, 4 cm trapezohedrons) and Bou Skour (Morocco, 5 cm crystals).

Bornite in France

In France, bornite is present at the Clausis copper mine near St-Véran (Hautes-Alpes) and in many other deposits associated with other sulphides and copper minerals.

Twinning and special crystallizations

Bornite commonly twins by interpenetration on {111}.

Fakes and treatments

No false identified for this mineral species.

Hardness : 3
Density : 5.06 to 5.09
Fracture : Irregular

Streak : Grey-black

TP : Opaque
IR : Not measurable
Birefringence : None
Optical character : None
Pleochroism : None
Fluorescence : None

Solubility : Nitric acid

Magnetism : Paramagnetic
Radioactivity : None


This service is used to secure web forms of our website and required if you want to contact us. By accepting it you agree to Google's privacy policy:

Google Analytics

Google Analytics is a service used on our website that tracks, reports traffic and measures how users interact with our website content in order for us to improve it and provide better services.


Our website allows you to like or share its content on Facebook social network. By activating and using it you agree to Facebook's privacy policy:


Integrated videos provided by YouTube are used on our website. By accepting to watch them you agree to Google's privacy policy:


Integrated tweets and share services of Twitter are used on our website. By accepting and using these you agree to Twitter's privacy policy:


Our website allows you to share its content on PInterest social network. By activating and using it you agree to PInterest's privacy policy: