A greasy, wax-yellow to reddish-brown weakly radioactive mineral, (Ce,La)(CO₃)F , most commonly found in contact zones, less often in pegmatites; found associated with allanite, cerite, tysonite, fluorite, and tornebohmite; hexagonal; obtained from Ryddarhyttan and Finbo, Sweden; Pikes Peak, CO, and Mountain Pass, CA.