 | | Journal (article/letter/editorial) | | there are only three operating Nbmines [Araxá and Catalão-II (Brazil) and St. Honoré (Canada)]. All produce...the primary sources. The Brazilian deposits at Araxá, Catalão-I and II, and Seis Lagos are examples of...Pekov, 2000) in the lujavrites of the Lovozero complex from which a concentrate with about 8 wt.% Nb2O5...Nb, due to the penchant for the element to form complex anions (NbO34 −; NbO76 −; Nb2O26 −) which cannot...Nb minerals whose structure is based upon these complex ions. Typically, basaltic rocks contain less than |  | Gomes, Celso de Barros, Comin-Chiaramonti, Piero, Azzone, Rogério Guitarrari, Ruberti, Excelso, Rojas, Gaston Eduardo Enrich (2018) Cretaceous carbonatites of the southeastern Brazilian Platform: a review. Brazilian Journal of Geology, 48 (2) 317-345 doi:10.1590/2317-4889201820170123 | Journal (article/letter/editorial) | | Universidade de São Paulo – USP, São Paulo (SP), Brazil. E-mails: cgomes@usp.br, rgazzone@usp.br, exrubert@usp...carbonatite occurrences of different regions of Brazil, Paraguay and Bolivia. Locality Occurrence Petrography...Petrography Mineralogy Age References BRAZIL Ribeira Valley 1 Barra do Itapirapuã Dike, vein, breccia..., Flo, Op (Hm, Il), Ch n.d. 75, 76 15 Araxá (Barreiro) Stock, dike Mg-ca, Ca-ca, Fe-ca Gl, Py,...Toniolo et al. (2013); 76, Monteiro et al. (2016); Araxá: 77, Issa Filho et al. (1984); 78, Traversa et al |  | Melgarejo, Joan C., Costanzo, Alessandra, Bambi, Aurora C.J.M., Gonçalves, Antonio O., Neto, Andrés B. (2012) Subsolidus processes as a key factor on the distribution of Nb species in plutonic carbonatites: The Tchivira case, Angola. Lithos, 152. 187-201 doi:10.1016/j.lithos.2012.06.024 | Journal (article/letter/editorial) | | conditions for mineral precipitation. Nb-rich rutile, gorceixite, Ba-rich K-feldspar and late Ba-poor K-feldspar...187–201 Fig. 1. Geological map of the Tchivira complex. J.C. Melgarejo et al. / Lithos 152 (2012) 187–201...economic point of view: the Seis Lagos deposit in Brazil, the largest Nb deposit in the world, has reserves...superposition of two or more of these processes produces complex mineral successions. The different types of alteration...Ma) riftogenic domain. 4. The Tchivira Complex The Tchivira Complex is a ring structure more than 12 km |  | | Journal (article/letter/editorial) | | Weathered crusts overlying carbonatite complexes in Brazil and one hard rock carbonatite deposit in Canada...currently Mibra Mine, Volta Grande (Brazil), the Pitinga Mine (Brazil) and Marropinno (Mozambique). The...Papp (2009a, 2011a, 2013a) 1200 1000 Australia Brazil Canada 800 Rwanda Mozambique 600 Other World...Russia and India. Production comes primarily from Brazil. Production from Canada and other 500 400 300...and Papp (2009a, 2011b, 2013b) 70000 60000 50000 Brazil 40000 Canada 30000 Other World Total 20000 |  | Smith, M.P., Moore, K., Kavecsánszki, D., Finch, A.A., Kynicky, J., Wall, F. (2016) From mantle to critical zone: A review of large and giant sized deposits of the rare earth elements. Geoscience Frontiers, 7 (3) 315-334 doi:10.1016/j.gsf.2015.12.006 | Journal (article/letter/editorial) | | the primary igneous source, but the grade is a complex function of igneous source, magmatic crystallisation...molal Na2O+K2O/Al2O3>1.2, and the formation of complex Zr and Ti minerals such as eudialyte – such rocks...host marble. The geochronology of the ores is complex, with periods defined from 1230– 1350 Ma (largely...2015). SC Bear Lodge– The Bear Lodge Carbonatite complex is not currently mined, but hosts potentially economic...by Moore et al. (2015). The Bear Lodge Alkaline Complex is part of the Black Hills Intrusive Belt, South |  | | Report (issue) | | rare-earth elements, and antimony in China; niobium in Brazil; and platinum-group elements in South Africa and...solubility of fluorite as a function of temperature for complex Na-Ca-Mg-Cl brines from ambient temperatures to...subsurface geology of the Saint-Honoré carbonatite complex in southern Quebec, Canada, and a schematic north-south...chart showing niobium resources and reserves in Brazil, Canada, and the United States...................showing the Rustenburg Layered Suite of the Bushveld Complex, South Africa, the surface trace of significant |
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