... of the SMD. Batches of anatectic melt accumulated and coalesced into a larger volume that subsequently formed the pegmatite. This is the first chemical evidence presented for the formation of an LCT type pegmatite by direct anatexis. Mt. Mica pegmatite pegmatite bulk composition anatexis Sebago...

..., they grade toward a distinct LCT-type signature (elbaite-bearing). The melts parental to the pegmatite bodies were more voluminous, more alkaline, less aluminous and less reduced than is the norm for melts parental to LCT-type pegmatite. Differentiation of these melts sequentially produced hornblende granite...

... is a weakly fractionated and geochemically primitive LCT-type pegmatite. The degree of differentiation of the pegmatite increases from the border to the core, as shown by a decrease of Fe/(Fe + Mn) in olivine-type phosphates, which decreases from 0.75 in the IWZ, to 0.71 in the IZ. Muscovite and tourmaline...

...Karen L. Marchal; William B. Simmons; Alexander U. Falster; Karen L. Webber; Encarnación Roda-Robles Abstract Mount Mica is a poorly zoned, sodic LCT-type pegmatite consisting dominantly of quartz, albite, and muscovite in the outer portion of the pegmatite. Micas are the principal K minerals...

... setting; in contrast, NYF (Nb–Y–F-enriched) pegmatites, are affiliated with anorogenic suites, formed in an extensional setting, and really not fundamentally different in petrogenetic lineage from suites in silica-undersaturated systems, including carbonatites. Both LCT and NYF types involve magmas...

...Ferdinando Bosi; Henrik Skogby; Giovanna Agrosì; Eugenio Scandale Abstract Tsilaisite, NaMn 3 Al 6 (Si 6 O 18 )(BO 3 ) 3 (OH) 3 OH, is a long-expected new mineral of the tourmaline supergroup. It occurs in an aplitic dike of a LCT-type pegmatite body from Grotta d’Oggi, San Pietro in Campo, island...

...Ferdinando Bosi; Giovanni B. Andreozzi; Giovanna Agrosì; Eugenio Scandale Abstract Fluor-tsilaisite, NaMn 3 Al 6 (Si 6 O 18 )(BO 3 ) 3 (OH) 3 F, is a new mineral of the tourmaline supergroup. It occurs in an aplitic dyke of a LCT-type pegmatite body from Grotta d'Oggi, San Piero in Campo, Elba...

... enriched in components representative of LCT pegmatites. A comparison of the relative molar abundances of the alkali elements versus aluminum shows significant overlap for granitic rocks from different tectonic settings. In orogenic settings, I-type granite is generally metaluminous, whereas S-type...

... and magmatic texture of the pegmatites. We show in this study that the pegmatites have a similar and characteristic geochemical and mineralogical signature on the regional scale and can be classified as differentiated beryl-columbite-phosphate LCT (lithium, cesium, tantalum) types in the most evolved cases...

... pétalite. Les travaux récents portant sur ce champ de pegmatites ont visé à caractériser les autres types de pegmatites, ainsi que la minéralisation complexe et les associations de minéraux. Les minéraux du groupe de la columbite sont présents dans toutes les pegmatites de type LCT (Li–Cs–Ta) à...

...Pura Alfonso; Joan Carles Melgarejo Abstract The Cap de Creus LCT granitic pegmatites, in Catalonia, northeastern Spain, belong to the beryl – columbite and beryl – columbite – phosphate subtypes and to the albite type. Fluid inclusions have been studied in all these types of pegmatite to determine...

...-phosphate minerals analyzed are from LCT and NYF pegmatite dikes of the Central Alps, which includes three main areas: Vigezzo (LCT and NYF from the Vigezzo valley), Bodengo (NYF from the Leggia valley and LCT from the Cama valley), and Codera (LCT from Codera and Chiavenna valleys and Alpe Rossaccio). SEM...

... granitic rocks. Using the nomenclature of Černý (1991) and Černý & Ercit (2005) , the pegmatites have a LCT signature and belong principally to the beryl, complex, albite and albite–spodumene types. § E-mail address : galliski@lab.cricyt.edu.ar 22 10 2005 03 10 2004...

... from I-type granites, and a mixed NYF + LCT family of diverse origins, such as contamination of NYF plutons by digestion of undepleted supracrustal rocks. Abstract Il y a eu plusieurs tentatives de classification de pegmatites granitiques au cours du siècle dernier, avec un taux de réussite et une...

...Andrew G. Tindle; Julie B. Selway; Fred W. Breaks Abstract Liddicoatite, a rare species of tourmaline, has been found in the McCombe pegmatite, of complex type and spodumene subtype, an example of the LCT (lithium, cesium, tantalum) family. It is one of a group of beryl- and complex-type pegmatites...

... pegmatite represents a special type of contaminated LCT pegmatite rather than a member of the mixed family. § E-mail address: mnovak@sci.muni.cz 02 07 2011 26 07 2012 © The Mineralogical Association of Canada 2012 Li-bearing pegmatites mixed (NYF + LCT) signature origin...

.... La pegmatite fortement fractionnée, membre de la famille des pegmatites LCT enrichie en éléments rares et de sous-type de la pétalite, contient neuf zones internes. Les zones externes sont concentriques, tandis que les zones internes sont segmentées et de forme localement complexe. Un modèle...

...Daniel J. Kontak; T. Kurtis Kyser Abstract The 395 Ma Brazil Lake granitic pegmatite, a rare occurrence of an LCT-type (Li–Cs–Ta) pegmatite in the Meguma Terrane of Nova Scotia, Canada, is hosted by metasedimentary and metavolcanic rocks of the Silurian White Rock Group. Previous mineralogical...

..., mainly Ti-dominant, are U-rich betafite (0.29–0.57 apfu U) and locally pyrochlore. The primary minerals are typical of an NYF-type pegmatite, and contrast with the LCT-type mineralogy (which includes abundant elbaite–liddicoatite, a pink variety of beryl, spodumene, and hambergite) typical of much...

... (Li–Be–Ta–Nb) et de type LCT, situées dans la province pegmatitique de Borborema (BPP), nordest du Brésil. Dans les zones de bordure et de paroi des pegmatites, la tourmaline est enrichie en Mg et Fe; les compositions sont des membres magnésiens de la solution solide entre dravite et schorl. Dans...