Bornite (Peacock ore)Cu5FeS4
Class: Sulfide Hardness: 3 Density: 5.0 - 5.1 Streak: Grayish black Lustre: Metallic Habit: Massive fine-grained aggregate. Colours: Iridescent purple, blue and black | | Crystal System: Orthorhombic Cleavage: Very poor Fracture: Conchoidal Magnetism: None Reaction with HCl: Very weak | Identification in hand sample: Green-blue-purple iridescence is indicative, as is a brownish-bronze colour on fresh surfaces. Associations: Very common in copper-bearing hydrothermal sulfide deposits. Associated with chalcopyrite, chalcocite, covellite, pyrrhotite and pyrite. Industrial / ecomonic uses: Mined as an ore of copper, but not as important as chalcopyrite. Comments: Pseudo-isometric. |