Charrier, Allier, Auvergne, France
The Charrier deposit was mined from 1870 to 1954 with some smaller interruption for copper, zinc, tin and silver. The main ore minerals are sphalerite and chalcopyrite, additionally it contains some bismuth minerals. Charrier is the type locality for roquesite which was discovered in 1955 and was the first IMA approved mineral. For comparison see also the Les Clochettes deposit.
Polished slab. The freshly broken rock is green and becomes almost black during polishing, which makes scanning difficult. Most of the ore minerals visible is sphalerite, in the lower part some weathered chalcopyrite can be seen. Width: 14 cm
The re-polished sample from REM-EDX with mainly grey sphalerite and yellow chalcopyrite with Nic //, Obj. 20x, air, 100 µm scale bar:
Note the finely distributed chalcopyrite, better known as „copper disease“ as separation from the sphalerite is very difficult to achieve; Nic //, Obj. 50x, air, 50 µm scale bar:
Finally, enlarged from the first picture with Nic //, Obj. 125x, oil:
Same as above. Ccp: Chalcopyrite, Sph: Sphalerite, Wit: Wittichenite, Roq: Roquesite. The later was confirmed by REM-EDX while the wittichenite might also be emplectite. At Charrier the roquesite is usually associated with wittichenite, therefore it was labelled as such.
For further informations on the region this article might be interesting:
Picot, P., Pierrot, R.: La roquésite, premier minéral d’indium: CulnS2. Bull Soc franc Miner Crist.86.(1933).7-14.