Atomic Positional Parameters
Cu 4a 0.0000 0.0000 0.0000
Fe 4b 0.0000 0.0000 0.5000
S  8d 0.2574 0.2500 0.1250

Reference
SR Hall and JM Stewart (1973) Acta Crystallographica B, 29, 579

Mineral Chemistry
Chalcopyrite is one of the most important copper bearing mineral phases, and is often associated with pyrite mineralisation. Secondary copper minerals in the supergene, or oxidised, zones of copper ores derive from alteration of chalcopyrite.

Chalcopyrite does not have the pyrite structure, but instead is based on a supercell of the sphalerite structure, with coppers and irons arranged in a regular fashion to give a tetragonal unit cell. Both copper and iron atoms are tetrahedrally coordinated by four sulphurs.

The CHIME figure shows copper as blue, iron as red, and sulphur as yellow spheres.