Chalcopyrite
Image: James Petts from London, England (CC BY-SA 2.0)
Mineral NameChalcopyrite
Chemical FormulaCuFeS2
Mohs Hardness3.5
Crystal Systemtetragonal
Lustermetallic
Streak Colorgreenish-black
Cleavagepoor/indistinct
Fractureuneven
Specific Gravity4.1
Colorsbrassy yellow, golden yellow, iridescent tarnish
Transparencyopaque
Type LocalityWorldwide in various ore deposits
Mineral GroupSulfides
Usesmajor copper ore, collector's specimens
Associated Mineralspyrite, sphalerite, galena, quartz, calcite
Raritycommon
Description
A metallic, brassy yellow mineral with patches of iridescent tarnish, embedded within a greyish-white rock matrix.
Geological Context
Chalcopyrite is the most important ore mineral of copper, typically found in hydrothermal veins, porphyry copper deposits, and massive sulfide deposits associated with igneous and metamorphic rocks.
