 | | Journal (article/letter/editorial) | | PYROCHLORE-GROUP MINERALS FROM THE LUESHE AND ARAXĂ (BARREIRO) CARBONATITES BY 57Fe MĂSSBAUER SPECTROSCOPY...Lueshe in the Democratic Republic of Congo, and AraxĂĄ in Brazil. In contrast to the common assumption that...O2â and 1 OHâ, whereas in bariopyrochlore from AraxĂĄ, the unusually large value of the quadrupole splitting...Republic of Congo, and the Barreiro carbonatitic complex at AraxĂĄ, in Brazil, using 57Fe Mössbauer spectroscopy...oxide spinels, where the ideal stoichiometry of a spinel is commonly assumed, but 57Fe Mössbauer spectroscopy |  | Cordeiro, Pedro F.O., Brod, JosĂ© A., Dantas, Elton L., Barbosa, Elisa S.R. (2010) Mineral chemistry, isotope geochemistry and petrogenesis of niobium-rich rocks from the CatalĂŁo I carbonatite-phoscorite complex, Central Brazil. Lithos, 118 (3) 223-237 doi:10.1016/j.lithos.2010.04.007 | Journal (article/letter/editorial) | | CatalĂŁo I carbonatite-phoscorite complex, Central Brazil Pedro F.O. Cordeiro a,â, JosĂ© A. Brod a,b, Elton...GeociĂȘncias, Universidade De BrasĂlia, BrasĂlia-DF, Brazil Instituto De Estudos Socio-Ambientais, Universidade...Universidade Federal De GoiĂĄs, GoiĂąnia-GO, Brazil a r t i c l e i n f o Article history: Received 28 July...Igneous Province (APIP), central Brazil, particularly in the CatalĂŁo I and AraxĂĄ carbonatite-bearing complexes...available by Mineração CatalĂŁo (Anglo American Brazil) from the CatalĂŁo I niobium deposit provide an |  | | 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 |  | | Report (issue) | | led by, in decreasing order of reserves, China, Brazil, Australia, and India (Gambogi, 2015). Australia...Western Australia, Australia, and AraxĂĄ in the State of Minas Gerais, Brazil). The principal REE minerals...20° 10° 0° 10° 20° 30° 40° 50° 60° 80° AraxĂĄ Buena Norte mining district Zandkopsdrift Lofdal...the AraxĂĄ deposit, which overlies the Barreiro carbonatite complex in the State of Minas Gerais, Brazil;...CatalĂŁo I carbonatite complex in the State of GoiĂĄs, Brazil; and the Mount Weld carbonatite in Western Australia |  | | Journal (article/letter/editorial) | | has previously been metasomatically enriched (Barreiro and Cooper, 1987). Crustal interaction is limited...and post-cumulus processes. Lithos, 31, 207-25. Barreiro, B.A. and Cooper, A.F. (1987) A Sr, Nd, and Pb...Southwest Namibia. Geology, 19, 1193-6. Cooper, A.F., Barreiro, B.A., Kimbrough, D.L. and Mattinson, J.M. (1987)...Carbonatites, Pocos de Caldas, Minas Gerais, Brazil. Ministerio das Minas e Energia, 188, 207-12. Gold...trace elements in olivine, pyroxenes, garnet and spinel. Trans. R. Soc. Edin., Eth. Sci., 77, 181-201. |  | | Report (issue) | | the Departmento National da Produ^ao Mineral of Brazil under the auspices of the Agency for International...Ferrifero, Minas Gerais, Brazil By NORMAN HERZ REGIONAL GEOLOGY OF THE QUADRILATERO FERRIFERO, MINAS GERAIS...GERAIS, BRAZIL GEOLOGICAL SURVEY PROFESSIONAL Prepared in cooperation with the Departmento Nacional da Produqao...Produqao Mineral of Brazil under the auspices of the Agency for International Development of the United...Ferrifero, Minas Gerais, Brazil. (Regional geology of the Quadrilatero Ferrifero, Minas Gerais, Brazil) (Geological |  | | Journal (article/letter/editorial) | | staurolite ± plagioclase ± biotite ± muscovite ± spinel with accessory rutile ± ilmenite ± pyrite ± monazite...mineral phases make up this assemblage. Garnet and spinel belong to an early generation, whereas kyanite...Copeland et al. 1988; Parrish 1990; Smith and Barreiro 1990; Kingsbury et al. 1993; Franz et al. 1996)...particularly valuable for dating metamorphism (Smith and Barreiro 1990; DeWolf et al. 1993; Kingsbury et al. 1993;...Composition of monazite from pegmatites of eastern Minas Gerais, Brazil. Geochim Cosmochim Acta 16: 1±14 Ni Y, Hughes |  | | Journal (article/letter/editorial) | | Otoni, Minas Gerais, Brazil, and 2 Departamento de QuıÌmica, ICEx, Universidade Federal de Minas Gerais...Gerais, 31270-901 Belo Horizonte, Minas Gerais, Brazil (Received 22 January 2012; revised 23 April 2012;...to magnetite. Magnetite (Fe3O4) has an inverse spinel structure with a face-centered cubic unit cell...positive charge. Maghemite thus is a cationdeficient spinel with Fe3+ on both the A and B sites. Because of...and contaminant decomposition in aqueous media. Barreiro et al. (2007) studied the oxidation of atrazine |  | GIBSON, S. A., THOMPSON, R. N., LEONARDOS, O. H., DICKIN, A. P., MITCHELL, J. G. (1995) The Late Cretaceous Impact of the Trindade Mantle Plume: Evidence from Large-volume, Mafic, Potassic Magmatism in SE Brazil. Journal of Petrology, 36 (1) 189-229 doi:10.1093/petrology/36.1.189 | Journal (article/letter/editorial) | | GEOCIENCIAS, UNIVERSIDADE DE BRASILIA, 70910 BRASILIA DF, BRAZIL 'DEPARTMENT OF GEOLOGY, McMASTER UNIVERSITY, is8o...plutonic comAlto Paranaiba Igneous Province, in SE Brazil, is one of the plexes at ~ 85 Ma. Reconstructions...is one Late Cretaceous alkaline magmatism in SE Brazil may have of several Cretaceous alkaline igneous...around the margin of the Parana sedimentary basin in Brazil subcontinental lithosphere. Heat penetrating the...from Large-volume, Mafic, Potassic Magmatism in SE Brazil JOURNAL OF PETROLOGY VOLUME 36 Potassic-rich |  | | Journal (issue) | | geology, and notable localities of diamond mining in Brazil, and outlines plans for future diamond production... Svisero, James E. Shigley, and Robert Weldon Brazil, which commanded global production in the 1700s...principally in the states of Minas Gerais and Mato Grosso, are presented. W hile Brazil is widely known for...Tijuco (later named Diamantina) in the state of Minas Gerais (CalĂłgeras, 1904; Leonardos, 1959; Barbosa,...and Bartorelli, 2010). For the next 150 years, Minas Gerais was the worldâs major supplier of gem diamonds |  | | Journal (issue) | | mining-themed park was approved in 2000, and the Minas de AlmadĂ©n y Arrayanes The Mineralogical Record...of the mines has been the responsibility of the Minas de AlmadĂ©n y Arrayanes (MAYASA), a State-owned company...was at that time Governor of the AlmadĂ©n mines (Barreiro, 1992). From 1776 to 1784, King Carlos III commissioned...others, several specimens of cinnabar from AlmadĂ©n (Barreiro, 1992). In 1791, the Assistant Director of the...Goethite Ilmenite (*) Lepidocrocite Montroydite Spinel (chromium rich) Fe31O(OH) Fe21TiO3 Fe31O(OH) HgO |  | | Journal (article/letter/editorial) | | and Jacob, 1979; Eriksson, 1984), as well as in Brazil (Issa Filho et al., 1984; Ribeiro et al., 2005;...quenched melt; Fl, fluid; Ol, olivine; Spi, magnetite spinel; Apt, apatite; Cc, calcite; Cpx, clinopyroxene...olivine; Apt, apatite; Cpx, clinopyroxene; Spi, spinel (magnetite). Quenched melt analyses were normalized...and Fe2O3 in spinel analyses was calculated assuming ideal crystal chemistry of spinel mounted in epoxy...compositions generally agree rather well with natural spinel, olivine and apatite compositions (e.g., Krasnova |  | Barreiro, J. GĂłmez, Lonardelli, I., Wenk, H.R., Dresen, G., Rybacki, E., Ren, Y., TomĂ©, C.N. (2007) Preferred orientation of anorthite deformed experimentally in Newtonian creep. Earth and Planetary Science Letters, 264 (1) 188-207 doi:10.1016/j.epsl.2007.09.018 | Journal (article/letter/editorial) | | deformed experimentally in Newtonian creep J. GĂłmez Barreiro a,â, I. Lonardelli a,b , H.R. Wenk a , G. Dresen...address: jgomezbarreiro@berkeley.edu (J. GĂłmez Barreiro). 0012-821X/$ - see front matter © 2007 Elsevier...âcrystallographic preferred orientationâ. J. GĂłmez Barreiro et al. / Earth and Planetary Science Letters 264...apparatus equipped with an internal 190 J. GĂłmez Barreiro et al. / Earth and Planetary Science Letters 264...data from (Rybacki and Dresen, 2000). J. GĂłmez Barreiro et al. / Earth and Planetary Science Letters 264 |  | | Journal (issue) | | iridescence observed in ârainbowâ hematite from Minas Gerais, Brazil. 40 DNA Techniques Applied to the Identification...iridescence in metamorphic ârainbowâ hematite from Brazil. The authors use electron microscopy, atomic force...colored by GR1 defects have been alluvial deposits in Brazil, Guyana, Venezuela, Zimbabwe, the Central African...never graded by GIA), and the 5.03 ct Aurora Green (Brazil), which sold at auction in 2016 for more than US...America has yielded a number of green diamonds from Brazil and Guyana (figure 7). Most show extensive surficial |  | | Journal (article/letter/editorial) | | They consist mainly of clinopyroxene, mica and spinel sensu lato (s.l.) but, adjacent to the mantling...developed that consists of new types of pyroxene and spinel that are chemically different from those in the...chosen for study. In BD 871 a dark-green pyroxene-spinel zone (PSZ) separates a mica pyroxenite (MP) core...Photomicrograph of pyroxene-spinel zone in BD871, showing (a) greater proportion of spinel in the PSZ vs. mica...of BD871. Note the preferential concentration of spinel in the dark, metasomatized parts of the grains |  | Murphy, J. Brendan, Cousens, Brian L., Braid, James A., Strachan, Rob A., Dostal, Jaroslav, Keppie, J. Duncan, Nance, R. Damian (2011) Highly depleted oceanic lithosphere in the Rheic Ocean: Implications for Paleozoic plate reconstructions. Lithos, 123 (1) 165-175 doi:10.1016/j.lithos.2010.09.014 | Journal (article/letter/editorial) | | McKerrow et al., 1990; Murphy et al., 2006; GĂłmez-Barreiro et al., 2007; Nance et al., 2010), which gave...Ri ve Atoy Chazumba Lithodeme Petlalcingo Las Minas Otate Mal Paso Palo Liso Ojo de Agua r Mimilulco...18Âș 30ÂŽN Amate Ordovician & ?older Salada Las Minas, Anacahuite, Huerta, Amate units Cosoltepec (ss)...J., FernĂĄndez-SuĂĄrez, J., Andonegui, P., GĂłmez-Barreiro, J., 2007b. Paleozoic ophiolites in the Variscan...systems. Earth Planet. Sci. Lett. 70, 221â236. GĂłmez-Barreiro, J., MartĂnez CatalĂĄn, J.R., Arenas, R., Castiñeiras |  | | Journal (article/letter/editorial) | | kimberlite groundmass in association with olivine, zoned spinel, phlogopite, carbonates (dolomite, calcite, magnesite)...Srpâserpentine; Dolâdolomite; Phlâphlogopite; Mgtâzoned spinel; Olâolivine; Tfpâtetraferriphlogopite. Ven-20,...worldwide (Kamenetsky et al., 2008). The presence of Cr-spinel crystals is not typical of olivine of this generation...garnet, Mnâilmenite, picroilmenite and chromian spinel, and peridotite microxenoliths are present (Kaminsky...olivine and phlogopite in an aggregate of zoned spinel, dolomite, phlogopiteâtetraferriphlogopite, calcite |  | | Journal (article/letter/editorial) | | 1967; Sawka et al., 1986; Parrish, 1990; Smith & Barreiro, 1990; Kingsbury et al., 1993). Unlike zircon...achieved and hence before anatexis occurs (Smith & Barreiro, 1990). The growth of metamorphic monazite in...near the P-T of the staurolite isograd (Smith & Barreiro, 1990; Kingsbury et al., 1993). Rarely, monazites...& Tirrul, 1989; Harrison et ul., 1990; Smith & Barreiro, 1990; Kingsbury et ul., 1993), support the interpretation...Koppel et al., 1980; Black et al., 1984; Eusden & Barreiro, 1988). At shallow crustal levels where high-T |  | | Journal (article/letter/editorial) | | Carbonatite complex 1 2 3 Amba Dongar Otjisazu AraxĂĄ Total (km2) 6.7 11.9 21.2 km2 3.2 0.9 7.0 % 47...Paleoproterozoic collision zone of the Borborema province, NE Brazil (EJ dos Santos et al. 2013; RV Santos et al. 2013);...Mount Weld, Australia (Lottermoser 1990) and AraxĂĄ, Brazil (Neumann and Medeiros 2015). The REE mineralisation...Nb (Figures 21(c, d) and 23 (a); e.g. CatalĂŁo, Brazil; Lueshe, Democratic Republic of Congo; and St....regolith (e.g. CatalĂŁo I, Brazil; Cordeiro et al. 2011; and AraxĂĄ, Brazil; Issa Filho et al. 2015). Although |  | Lucassen, Friedrich, Franz, Gerhard, Romer, Rolf L., Schultz, Frank, Dulski, Peter, Wemmer, Klaus (2007) Pre-Cenozoic intra-plate magmatism along the Central Andes (17â34°S): Composition of the mantle at an active margin. Lithos, 99 (3) 312-338 doi:10.1016/j.lithos.2007.06.007 | Journal (article/letter/editorial) | | Ma; P = 1.0 GPa; 900 °C; Lucassen et al., 1999). Spinelâ lherzolite xenoliths from the same location indicate...the upper mantle comes from the composition of spinel lherzolite xenoliths in the late Cretaceous basanite...and regionally more variable (e.g., Tilton and Barreiro, 1980; Macfarlane et al., 1990; Aitcheson et al...which could be explained either by garnet free spinel lherzolite or small amounts of garnet in the mantle... Arequipa Massif of southern Peru; Tilton and Barreiro (1980). The xenoliths show a similar range of |  | | Journal (article/letter/editorial) | | Melt compositions point to an amphibole-bearing spinel facies lithospheric mantle source enriched by metasomatism...that indicate a HIMU-like source component (e.g. Barreiro and Cooper, 1987; Baker et al., 1994; Hoernle...Nd(i) = +3.5 to +8.5 and Δ Hf(i) = +3.3 to +10.9 (Barreiro and Cooper, 1987; Baker et al., 1994; Hoernle...been partially constrained through examination of spinel facies peridotite xenoliths and outcrops. The orogenic...(peridotite + amphibole ± trace phases melting at spinel facies) being the main compet- ing models. Several |  | | Journal (article/letter/editorial) | | be modelled in two steps, (1) partial melting of spinel lherzolite to produce picritic basalt, and (2)...generated in the asthenosphere by partial melting of spinel lherzolite and that the parental magma fractionated...isotopic analyses are detailed in Bevier (1982a) and Barreiro (1982). The measurements were performed on a 35...Frey et al. (1978) used the presence of included spinel lherzolite nodules, Mg values, and abundances of...89-6 Mode Olivine Orthopyroxene Clinopyroxene Spinel Picrite (PL) derivedfrom 43 per cent melting |  | Lucassen, Friedrich, Escayola, Monica, Romer, Rolf L., Viramonte, JosĂ©, Koch, Kerstin, Franz, Gerhard (2002) Isotopic composition of Late Mesozoic basic and ultrabasic rocks from the Andes (23â32°S) â implications for the Andean mantle. Contributions to Mineralogy and Petrology, 143 (3) 336-349 doi:10.1007/s00410-001-0344-3 | Journal (article/letter/editorial) | | Cenozoic Andes, and the ParanaÌ basin in south-east Brazil and surrounding areas. Sample sites are marked...centres; with phenocrysts and deformed xenocrysts, spinelâlherzolite and lower crustal xenolithsi,k,l,m fragments...fractured olivine xenocrysts; matrix with reported; spinelâlherzolite and crustal xenoliths melilite, perovskite...southern Peru and in western Bolivia (Tilton and Barreiro 1980; Tosdal 1996; WoÌrner et al. 2000). These...initial values. Arequipa Massif from Tilton and Barreiro (1980), other data sources as in Fig. 5 SigniïŹcant |  | | Journal (article/letter/editorial) | | U-Th-Pb, Rb-Sr, Sm-Nd and Re-Os isotopic dataset for spinel peridotite xenoliths sampling 8 the subcontinental...lherzolites and are 134 exclusively from the spinel-facies with equilibration temperatures varying...Alpine Dyke Swarm 203 (206Pb/204Pb = 19.9-20.3; Barreiro and Cooper, 1987). These basalts show variability...to carbonatites found in the Alpine Dyke Swarm (Barreiro and Cooper, 306 1987) and pristine oceanic carbonatites...lack of coupled U-Th and 520 Pb isotopic data (Barreiro and Cooper, 1987; Cooper, 1986; Cooper and Paterson |  | | Book | | BARTORELLI ::âą . . .. MINERALS & PRECIOUS STONES OF BRAZIL Sponsored by: VALE MINISTER.IO DA CULTURA ©...Lavra do Sapo, Ferruginha, Conselheiro Pena, Minas Gerais. Collection of Alvaro Lucio. Photograph taken...Brasileira do Livro, SP, Brazil) Cornejo, Carlos .Minerals & precious stones of Brazil. Carlos Cornejo, Andrea...3. Minerals - Brazil 4. Minerals- Classification 5. Mineralogy 6. Mineralogy - Brazil - History 7. Precious...Precious stones - Brazil I. Bartorelli, Andrea. II. Title. 09-10025 Cover photograph: Crystal of brazilianite |
|
