Les Montmins Mine (Ste Barbe vein), Echassières, Ebreuil, Allier, Auvergne, France

Early 20th century tungsten mine, working hübnerite-bearing quartz veins hosted by micaceous slates. Located about 3 km NE of Echassières.
Famous for a wealth of well-crystallised secondary oxysalt minerals (mainly phosphates and arsenates).

Refs.:
- Aubert, G. (1969): Les coupoles granitiques de Montebras et d'Echassières (Massif Central Français) et la genèse de leurs minéralisations en étain, lithium, tungtène et béryllium. Mémoires du BRGM N°46, 345 pp.
- Walenta, K. & Binder, W. (1980): Kidwellit und Dufrenit aus den Mines de Montmins bei Echassiéres (französisches Zentralmassiv). Aufschluss 31, 51-54.
- Boisson, J.-M., Leydet, J.-C., Queneau, P., Revel, C. & Valverde, J. (2000): Filon Sainte-Barbe, Commune d'Echassières (Allier, France). Le Cahier des Micromonteurs, No. 4, 3-46. (in French)
- Cuchet, S., Brugger, J., Meisser, N., Ansermet, S. & Chiappero, P.-J. (2000): Les minéraux du filon Sainte-Barbe, Les Montmins, Allier. Le Règne Minéral, (33), 5-25. (in French) [http://www.strahlen.org/magspublic/lrm/lrm-2000-0506-05-frankrijk-allier-montmins.pdf]
- Kolitsch, U., in preparation. [article on several new finds, will be submitted in autumn 2008 to Lapis magazine; some of the new finds are already listed here]

- http://www.strahlen.org/vp/fr/montmins/montmins.htm


NOTE on the published mineral photos:
- The photo of "mawbyite" published in Boisson et al. (2000) most probably shows a carminite. Single-crystal XRD studies of crystals with identical shape showed them to be carminite (Uwe Kolitsch, unpublished results).
- The dufrenites shown may in part be natrodufrenite (probably none of them has been analysed (semi-)quantitatively).