Chalcopyrite is always opaque so it should not exhibit asterism.
It is a common ore mineral that is sold by the ton, so simulants and synthetics probably do not exist.
Occasionally chalcopyrite displays iridescence, usually from a natural tarnish. However, sometimes people treat chalcopyrite with acid to produce a spectacular iridescence. The treated material is then sold as “peacock ore” or as a simulant of the mineral bornite.
You can find more information here https://geology.com/minerals/chalcopyrite.shtml
(disclosure: I am the author of that article)