When coupled with umangite, the mineral forms lath-shaped slender and elongated grains averaging 20 by 50 micrometers.

When exposed to polarized light, it displays a range of colors varying from creamy white to dark blue.

The display of these distinct colors, along with its reflectivity, allows athabascaite to be easily distinguished from other copper selenide minerals.

[7] After being discovered in Canada, a few other samples have been found in Petrovice, Vysočina Region, Predborice, and Koksin Hill, Czech Republic; Puy-de-Dôme, France; Kalmar, Sweden; La Rioja Province, Argentina; and most recently Zaire (Democratic Republic of Congo); all of which were found in or near uranium mines.

In the Czech Republic, it occurs with berzelianite, eucairite, crookesite, tyrrellite, ferroselite, bukovite, krutaite, calcite and dolomite.