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,
Pentlandite Thompson Belt, Canada, and a few examples from Brazil. Pentlandite, but primarily chalcopyrite and PGEs, are also obtained from the supergiant Norilsk nickel deposit, in trans-Siberian Russia. The Sudbury Basin in Ontario, Canada, is associated with a large meteorite impact crater. The pentlandite-chalcopyrite-pyrrhotite ore around the Sudbury Structure formed from sulfide melts that segregated from the melt sheet produced by the impact. Pentlandite is a catalyst for production of hydrogen and oxygen from water using electricity. It is said to be as effective at this as platinum, which is significantly rarer and more expensive. Pentlandite Pentlandite is an iron-nickel sulfide,