COPPER-PYRITES, or Chalcopyrite, a copper iron sulphide (CuFeS2), an important ore of copper.
Chalcopyrite or copper-pyrites may be readily distinguished from iron-pyrites (or pyrites), which it somewhat resembles in appearance, by its deeper colour and lower degree of hardness: the former is easily scratched by a knife, whilst the latter can only be scratched with difficulty or not at all.
An extremely important variety of pyrites is that which is more or less cupriferous, and is commonly known commercially as "copper-pyrites" (q.v.), though distinct mineralogically from that mineral.
From copper-pyrites (chalcopyrite) iron-pyrites is distinguished by its superior hardness and by its paler colour.