Geology of Mauritania ore. A Neoproterozoic carbonate unit, part of a synformal nappe overturned in the Paleozoic, now forms a major copper deposit 250 kilometers northeast of Nouakchott in the Mauritanides Belt. The one kilometer, 250 meter wide deposit spans the West and East Moghrein Guelb hills. Forty meters below the deposit is a secondary deposit of cuprite, azurite, malachite and tenorite, with an additional 2.25% copper, some gold and sulfide mineralization including cubanite, chalcopyrite, pyrrohitite and aresnopyrite. In the 2000s, mining at the site had mostly ceased except for gold mining in the tailings pile. Gypsum is extracted from the N'Drahamcha quarry,
Neuil mine by sphalerite, pyrite and chalcopyrite. The ore therefore belongs to the mineralisation type "sphalerite-pyrite-galena-chalcopyrite". A radiometric lead isotope study on the basement lodes yielded an age of 300 to 250 million years BP (Lougnon, J. et al. 1974). The lodes belong clearly to a late Variscan phase and were definitely formed after the intrusion of the Piégut-Pluviers Granodiorite into the paragneisses during the late Pennsylvanian (elsewhere lodes can be found that also formed within the granodiorite). Yet the metal impregnation is most likely genetically related to the granodiorite. The spatial arrangement of the lodes points towards local southeasterly extension within