|Latitude & Longitude (WGS84):||42° 48' 15'' North , 1° 48' 9'' East|
|Latitude & Longitude (decimal):||42.80444,1.80250|
|Name(s) in local language(s):||Carrière de talc de Trimouns|
|Other/historical region names associated with this locality:||Midi-Pyrénées|
Note Hoshino et al. (2008) have investigated the composition of dissakisite-(Ce) and allanite-(Ce) from this locality, and also publish 10 microprobe analyses from a single crystal. Their conclusion is that: Euhedral dissakisites from Trimouns dolomite mine, France, is compositionally-zoned. Back-scattered electron (BSE) images reveal that each of the described dissakisite crystals has three distinct compositional zones: normal zoned core (Mg-rich), oscillatory zoned middle (Ca-Al-rich) and homogeneous rim (Fe-ΣREE-rich). The latter zone with Fe2+> Mg corresponds to allanite-(Ce). Dissakisite-(Ce) also displays pronounced zoning in Fe/Mg which may suggest that the temperature of crystallization continuously decreased from core to rim. Each individual crystal will probably therefore contain both species. Allanite-(Ce) is generally considered to be darker than dissakisite-(Ce), but this is not a definitive way to distinguish between the minerals.
52 valid minerals. 2 (TL) - type locality of valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
443.8 - 541 Ma
|Cambrian-Ordovician intrusive and metamorphic terranes|
Age: Paleozoic (443.8 - 541 Ma)
Comments: Mixtures of metamorphic and intrusive or plutonic rocks, tracts known as crystalline, migmatitic terranes, moderately to highly metamorphosed rocks of unknown origin with or without intrusions. This classification is inherently prone to variable interpretation, as other compilers might distinguish some packages by their metamorphic or gneissic protoliths, and the associated age ranges may be more variable.
Lithology: Intrusive and metamorphic terranes
Reference: Geological Survey of Canada. Generalized geological map of the world and linked databases. doi:10.4095/195142. Open File 2915d. 
- de Parseval, P., Fontan, F., Aigouy, T. (1997): Composition chimique des minéraux de terres rares de Trimouns (Ariège, France). C. R. Acad. Sc. Paris, 234, Sér. IIa, 625-630.
- Marty, F. (2004). The Trimouns quarry, Luzenac - Ariège - France. The Mineralogical Record, 35(3), 225-247; 274.
- Gatel, P. , Parodi, G. , Parseval (De), P. , Fontan, F. and Marty, F. (2002). Les minéraux de terres rares à Trimouns. Le Règne Minéral (Hors série 8), 29-63.
- Gatel, P. , Parodi, G. , Parseval (De), P. and Fontan, F. (2002). Les minéraux de terres rares (T.R.). Le Règne Minéral (Hors série 8), 20-28.
- Gatel, P. and Marty, F. (2002). Autres espèces de Trimouns. Le Règne Minéral (Hors série 8), 64-76.
- Gatel, P. (2006). La trimounsite-(Y) de Trimouns, Luzenac (Ariège). Le Cahier des Micromonteurs(93), 122-123.
- Hoshino, M., Kimata, M., Nishida, N., Shimizu, M. (2010): Dissakisite-(Ce) chemical composition: some implications for its origin. Phys. Chem. Minerals 37, 255-263.