TC230AD: Group of doubly terminated crystals of the isomorphous series Dissakisite-(Ce)/Allanite-(Ce). The majority of Trimouns specimens present color zoning that seems to indicate the presence of both species in the same crystal, the darkest areas corresponding to Allanite-(Ce), as they are richer in iron, and the dominant lighter areas to Dissakisite-(Ce). On matrix, with white rhombohedral Dolomite crystals.
Trimouns Mine, Luzenac, Haute-Ariège, Foix, Ariège Department, Occitanie  France

Specimen size: 6 × 3.8 × 3.6 cm = 2.36” × 1.50” × 1.42”

Main crystal size: 1.1 × 0.1 cm = 0.43” × 0.04”