Chalcopyrite
Chalcopyrite is a sulfide mineral known for its striking metallic crystals, with several world-class Chinese localities.
About Chalcopyrite
Chalcopyrite is a sulfide mineral in the chalcopyrite group and has the chemical formula CuFeS₂. It crystallizes in the tetragonal system and is one of the most visually varied minerals in the collector market. Its combination of structural character and global distribution make it a recognized species in both systematic and aesthetic collections.
Identification & care
Chalcopyrite typically forms tetrahedral; massive (most common); granular; botryoidal (rare). Its color range is broad, including brass-yellow on fresh surface, tarnishes to iridescent purple, blue, red, and green (called 'peacock ore' when iridescent). The luster is metallic, the streak is greenish-black, and specimens are typically opaque. The cleavage is poor on {112}. The fracture is irregular/uneven, which aids identification.
Collector context
How it forms
In terms of geology, Chalcopyrite forms in hydrothermal veins; porphyry copper deposits; skarn; volcanogenic massive sulfide. It is commonly found in association with pyrite, sphalerite, galena, bornite, quartz, calcite.
Classic Chinese localities
**Jiama Cu-polymetallic deposit**, **Dexing Cu-Mo-Au ore field** and **Huanggang Fe-Sn deposit** are an important Chinese source for the species.
Why collectors care
Collectors gravitate to Chalcopyrite for the drama of its metallic luster and the geometry of its crystals — long striated blades, parallel sprays, or radiating clusters depending on the specimen. A large terminated group of chalcopyrite with intact luster is a centerpiece-level display object, and Chinese localities (where relevant) have produced some of the world's best-preserved material.
What affects value
Value in Chalcopyrite is assessed, in typical order of weight, against: (1) locality provenance; (2) crystal size; (3) termination quality and crystal completeness; (4) metallic luster integrity (absence of tarnish); (5) crystal habit elegance (parallel, radiating, or bladed); (6) matrix contrast and aesthetic balance; (7) condition and absence of re-attached crystals. Verified locality documentation and absence of cleaning residue act as strong multipliers across the above.
Naming history
The name Chalcopyrite has a specific etymological and historical context — see Mindat's reference entry for provenance details. We have retained naming data at the record level; published prose is paraphrased from factual fields rather than copied from source.