 | TorrĆ³, L., Villanova, C., Castillo, M., Campeny, M., GonƧalves, A. O., Melgarejo, J. C. (2012) Niobium and rare earth minerals from the Virulundo carbonatite, Namibe, Angola. Mineralogical Magazine, 76 (2) 393-409 doi:10.1180/minmag.2012.076.2.08 | Journal (article/letter/editorial) | | and rare earth minerals from the Virulundo carbonatite, Namibe, Angola L. TORROĢ1, C. VILLANOVA1, M. CASTILLO1...Agostinho Neto, Av. 4 de Fevereiro 7, 815 Luanda, Angola [Received 27 January 2011; Accepted 7 July 2011;...Editor: Hilary Downes] ABSTRACT The Virulundo carbonatite in Angola is one of the largest in the world...minerals (mainly synchysite-(Ce), britholite-(Ce), britholite-(La), cerite(Ce)). Cerium separated from...WORDS : Angola, carbonatite, pyrochlore, REE, magmatic, hydrothermal, weathering, Virulundo. Introduction |  | | Journal (article/letter/editorial) | | Monte Verde CarbonatiteāAlkalineāAgpaitic Complex (Angola) Sandra Amores-Casals 1,2, *, Antonio Olimpio GonƧalves... Caixa Postal 815, Angola; tonygoncalves72@hotmail.com Institut de CiĆØncies de la Terra Jaume Almera...agpaitic minerals; eudialyte; rinkite; loparite; Angola 1. Introduction Undersaturated alkaline rocks...one of the least studied carbonatite complexes in Angola. As a few studies have reported, the Monte Verde...structure, such as Tchivira [25,26], Bonga [26ā30], Virulundo [31], Bailundo [32], and Catanda [33]. Therefore |  | | Journal (article/letter/editorial) | | early-crystallizing phase in all rocks, whilst britholite crystallized during later magmatic stages in...gap between apatite and britholite, ranging from ~10 to 48 % of the britholite component. The dominant...apatite and britholite and is ascribed to kinetic effects. Key-words: apatite group, britholite group, Palaeogene...degree of solid solution between apatite and britholite. As part of an ongoing study of accessory phases...apatite-supergroup members, specifically fluorapatite and britholite. Relatively few studies of the variations in |  | Uher, Pavel, Ondrejka, Martin, BaÄĆk, Peter, Broska, Igor, KoneÄnĆ½, Patrik (2015) Britholite, monazite, REE carbonates, and calcite: Products of hydrothermal alteration of allanite and apatite in A-type granite from StupnĆ©, Western Carpathians, Slovakia. Lithos, 236. 212-225 doi:10.1016/j.lithos.2015.09.005 | Journal (article/letter/editorial) | | journal homepage: www.elsevier.com/locate/lithos Britholite, monazite, REE carbonates, and calcite: Products...16 September 2015 Keywords: Allanite Apatite Britholite REE carbonates Monazite Granite hydrothermal...on process to the britholite group mineral members: ļ¬uorbritholite-(Y), britholite-(Y), ļ¬uorcalciobritholite...hydroxyl-dominant analogue (ācalciobritholiteā). Britholite-(Y) contains up to 5.2 wt.% ThO2 (0.15 apfu Th);...Wood and Ricketts, 2000). On the other hand, britholite group minerals isostructural to the apatite group |  | Melgarejo, Joan C., Costanzo, Alessandra, Bambi, Aurora C.J.M., GonƧalves, Antonio O., Neto, AndrĆ©s 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) | | species in plutonic carbonatites: The Tchivira case, Angola Joan C. Melgarejo a, Alessandra Costanzo b,ā, Aurora...Geologia, Universidade Agostinho Neto, Luanda, Angola a r t i c l e i n f o Article history: Received...Tchivira carbonatite, located 400 km south of Luanda (Angola), is a good example of a carbonatite body produced...Nb (Nb, LĪ±); SnO2 (Sn, LĪ±); barite (Ba, LĪ±); LaB6 (La, LĪ±); CeO2 (Ce, LĪ±); REE1 glass (Pr, LĪ²); REE4 glass...Ti, 0.04; Fe, 0.08; Sr, 0.08; Zr, 0.17; Nb, 0.18; La, 0.11; Ta, 0.3; Pb, 0.51; Th, 0.16; U, 0.25; K, 0 |  | Zozulya, Dmitry, Lyalina, Lyudmila, Macdonald, Ray, BagiÅski, BogusÅaw, Savchenko, Yevgeny, Jokubauskas, Petras (2019) Britholite Group Minerals from REE-Rich Lithologies of Keivy Alkali GraniteāNepheline Syenite Complex, Kola Peninsula, NW Russia. Minerals, 9 (12) 732 doi:10.3390/min9120732 | Journal (article/letter/editorial) | | minerals Article Britholite Group Minerals from REE-Rich Lithologies of Keivy Alkali GraniteāNepheline...abundant (some of economic importance) and diverse britholite group minerals. The REE and actinides distribution...lithologies are proposed. Fluorbritholite-(Y) and britholite-(Y) from products of alkali granite (mineralized...resulting in crystallization of fluorbritholite-(Ce). Britholite group minerals (mainly fluorcalciobritholite...Si4+ = Ca2+ + P5+ , showing the full range of ābritholiteā and ācalciobritholiteā compositions up to theoretical |  | | Journal (volume) | | obtained on whole-rock samples and insitu by EMPA and LA-ICP-MS methods applied to primitive melt-inclusions...H2O. It can be done, however, by combining EPMA, LA-ICP-MS, micro-FTIR, and SC-XRD analyses. Pezzottaite...concentrations in the pearls were measured in situ by LA-ICP-MS. This method allows simultaneous measurement...compositions were measured in situ in the pearls by LA-MC-ICP-MS to explore the potential of this geochemical...ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). With spot analysis of 100 Ī¼m in diameter |
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