Chalcopyrite
Sulfide · CuFeS₂
Chalcopyrite is a copper iron sulfide and the most important ore of copper, recognisable by its brassy colour and peacock iridescence.
What is chalcopyrite?
Chalcopyrite is a copper iron sulfide and the world’s main copper ore. It is brass-yellow, often deeper and more golden than pyrite, and frequently tarnishes to an iridescent peacock blue-purple. It is notably softer than pyrite, which is the quickest way to tell the two apart.
Properties
- Chemical formula
- CuFeS₂
- Category
- Sulfide
- Hardness (Mohs)
- 3.5–4
- Crystal system
- Tetragonal
- Lustre
- Metallic
- Streak
- Greenish-black
- Colour
- Brass-yellow, often iridescent
- Cleavage / fracture
- Poor
How to identify chalcopyrite
- →Brassy to golden yellow, commonly with blue-purple iridescent tarnish.
- →Hardness only 3.5–4: a knife scratches it (pyrite will not scratch).
- →Greenish-black streak.
- →Massive or as small wedge-shaped crystals.
Where chalcopyrite is found
Chalcopyrite occurs in copper deposits worldwide, including the USA, Mexico, Peru, Chile and across Europe.
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Real specimens catalogued by collectors.
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