Bornite
Image: <a href="//commons.wikimedia.org/wiki/User:Islam90" title="User:Islam90">Islam90</a> (CC BY-SA 4.0)
Mineral NameBornite
Chemical FormulaCu₅FeS₄
Mohs Hardness3
Crystal Systemorthorhombic
Lustermetallic
Streak Colorgrayish black
Cleavagepoor on {111}
Fractureuneven to conchoidal
Specific Gravity5
Colorscopper-red, bronze-brown, purple, blue, black
Transparencyopaque
Type LocalityButte, Montana, USA
Mineral GroupSulfides
Usesore of copper, collector
Associated Mineralschalcopyrite, pyrite, chalcocite, covellite, enargite
Raritycommon
Description
This microscopic image displays a polished section of bornite, showing a relatively uniform, light metallic surface with numerous fine scratches and some darker inclusions. The overall appearance is typical of a metallic ore mineral under reflected light.
Geological Context
Bornite is a common primary copper ore mineral found in a variety of geological settings, including hydrothermal veins, porphyry copper deposits, and contact metamorphic deposits, often associated with other sulfide minerals.
