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Xenotime-(Y) and Sn-rich thortveitite in miarolitic pegmatites from Baveno, Southern Alps, Italy

Published online by Cambridge University Press:  05 July 2018

A. Guastoni
Affiliation:
Department of Geosciences, University of Padova, Via Gradenigo 6, I-35131 Padova, Italy
F. Nestola*
Affiliation:
Department of Geosciences, University of Padova, Via Gradenigo 6, I-35131 Padova, Italy
C. Ferraris
Affiliation:
Laboratoire de Minéralogie et Cosmochimie Muséum National d’Histoire Naturelle, Rue Buffon 61, CP52, 75005 Paris, France
G. Parodi
Affiliation:
Laboratoire de Minéralogie et Cosmochimie Muséum National d’Histoire Naturelle, Rue Buffon 61, CP52, 75005 Paris, France

Abstract

Xenotime-(Y), (Y,REE)PO4, and thortveitite, (Sc, Y)2Si2O7, in a miarolitic cavity in a niobium, yttrium, fluorine (NYF) granitic pegmatite at Baveno, Verbania, Southern Alps, Italy, were investigated by electron microprobe analysis and single-crystal X-ray diffraction. Fluorine has an important role as a complexing agent for Y and REEs in supercritical pegmatitic fluids; annitesiderophyllite and chamosite are the most likely sources of the Y and REEs. The thortveitite from Baveno contains up to 3.20 wt.% SnO2, an unusually high Sn content. Xenotime-(Y) is enriched in Gd in comparison to other Alpine xenotimes. Quantitative chemical data and measurements of the lattice parameters show that a higher scandium content results in a smaller unit-cell volume in thortveitite. The substitution of REEs for Y up to ∼20 mol.% has little effect on the unit cell of xenotime-(Y). The textures of xenotime-(Y) and thortveitite provide information about the dissolution and crystallization processes in the miarolitic cavity.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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References

Aldred, A.T. (1984) Cell volumes of APO4, AVO4, and ANbO4 compounds, where A = Sc, Y, La-Lu. Act Crystallographica, B40, 569574 CrossRefGoogle Scholar
Barzan, G. (1853) Il granito di Baveno. Giornale del Regio Istituto Lombardo di Scienze, Lettere e Arti. Milano, 23, 417433 Google Scholar
Bianchi, R., Pilati, T., Diella, V., Gramaccioli, C.M. and Mannucci, G. (1988) A re-examination of thortveitite. America. Mineralogist, 73, 601607 Google Scholar
Bilal, B.A. and Langer, P. (1987) Complex formation of trace elements in geochemical systems: stability constants of fluoro complexes of the lanthanides in a fluorite bearing model system up to 200ºC and 1000 bar. Inorganica Chimic. Acta, 140, 297298 Google Scholar
Boriani, A., Caironi, V., Oddone, M. and Vannucci, R. (1988) Some petrological and geochemical constraints on the genesis of the Baveno-Mottarone and Montorfano plutonic bodies. Rendiconti Societá Italiana di Mineralogi. Petrologia, 43, 385394 Google Scholar
Boriani, A., Giobbi Origoni, E. and Pinarelli L. (1995) Paleozoic evolution of southern Alpine crust (northern Italy) as indicated by contrasting granitoid suites. Lithos, 35, 4763.CrossRefGoogle Scholar
Cerný, P. and Ercit, S. (2005). The classification of granitic pegmatites revisited. The Canadian Mineralogist, 43, 20052026 CrossRefGoogle Scholar
Cetiner, Z.S., Wood, S.A. and Gammons, C.H. (2005) The aqueous geochemistry of the rare earth elements. Part XIV. The solubility of rare earth element phosphates from 23 to 150ºC. Chemical Geology, 217, 147169 CrossRefGoogle Scholar
Demartin, F., Pilati, T., Diella, V., Donzelli, S., Gentile, P. and Gramaccioli, C.M. (1991) The chemical composition of xenotime from fissures and pegmatites in the Alps. The Canadian Mineralogist, 29, 6975.Google Scholar
Gramaccioli, C.M., Diella, V., Demartin, F., Orlandi, P. and Campostrini, I. (2000a) Cesian bazzite and thortveitite from Cuasso al Monte, Varese, Italy: a comparison with the material from Baveno, and inferred origin. The Canadia. Mineralogist, 38, 14091418 CrossRefGoogle Scholar
Gramaccioli, C.M., Diella, V. and Demartin, F. (2000b) The formation of scandium minerals as an example of the role of complexes in the geochemistry of rare earths and HFS elements. European Journal of Mineralogy, 12, 795808 CrossRefGoogle Scholar
Guastoni, A. (2012) LCT (Lithium, Cesium, Tantalum) and NYF (Niobium, Yttrium, Fluorine) pegmatites in the Central Alps. Proxies of exhumation history of the Alpine nappe stack in the Lepontine dome. Unpublished PhD Thesis, XXIV cycle, University of Padova, Padova, Italy.Google Scholar
Guastoni, A. and Nestola, F. (2010) Sn-rich thortveitite intergrowth with xenotime-(Y): Y versus Sc fractionation in NYF miarolitic pegmatites at Baveno (Southern Alps, Italy). Acta Mineralogica- Petrographica, 20th General Meeting, IMA, Budapest, Ungheria, Abstract Volume 6, 616.Google Scholar
Guastoni, A. and Pezzotta, F. (2004) Kristiansenite a Baveno, secondo ritrovamento mondiale della specie. Rivista Mineralogic. Italiana, 30, 247251 Google Scholar
Guastoni, A., Nestola, F. and Giaretta, A. (2009) Mineral chemistry and alteration of rare earth element (REE) carbonates from alkaline pegmatites of Mount Malosa, Malawi. America. Mineralogist, 94, 12161222 CrossRefGoogle Scholar
Hsu, L.C. (1992) Synthesis and stability of bastnaesites in a part of the system (Ce,La)-F-H-C-O. Mineralogy an. Petrology, 47, 87101 CrossRefGoogle Scholar
Keppler, H. (1993) Influence of fluorine on the enrichment of high field strength trace elements in granitic rocks. Contributions to Mineralogy an. Petrology, 114, 479488 Google Scholar
Kosterin, A.V. (1959) The possible modes of transport of the rare earths by hydrothermal solutions. Geochemistr. International, 4, 381387 Google Scholar
Liu, X. and Byrne, R.H. (1997) Rare earth and yttrium phosphate solubilities in aqueous solution. Geochimica et Cosmochimica Acta, 61, 16251633 CrossRefGoogle Scholar
London, D. (1987) Internal differentiation of rareelement pegmatites: effects of boron, phosphorous, and fluorine. Geochimica et Cosmochimica Acta, 51, 403420 CrossRefGoogle Scholar
London, D (1992) The application of experimental petrology to the genesis and evolution of granitic pegmatites. The Canadia. Mineralogist, 30, 499540 Google Scholar
London, D. (1997) Estimating abundances of volatile and other mobile components in evolved silicic melts through mineral-melt equilibria. Journal of Petrology, 38, 16911706 CrossRefGoogle Scholar
London, D. (2005) Granitic pegmatites: an assessment of current concepts and directions for the future. Lithos, 80, 201303 CrossRefGoogle Scholar
London, D. (2008) Pegmatites. Canadian Mineralogist Special Publication 10. Mineralogical Association of Canada, Québec, Canada, 347 ppGoogle Scholar
London, D., Wolf, M.B., Morgan, G.B. VI and Garrido M.G. (1999) Experimental silicate-phosphate equilibria in peraluminous granitic magmas, with a case study of the Alburquerque batholith at Tres Arroyos, Badajoz, Spain. Journal of Petrology, 40, 215240 CrossRefGoogle Scholar
Mogilevsky, P., Zaretsky, E.B., Parthasarathy, T.A. and Meisenkothen, F. (2006) Composition, lattice parameters, and room temperature elastic constants of natural single crystal xenotime from Novo Horizonte. Physics an. Chemistry of Minerals, 33, 691698 CrossRefGoogle Scholar
Ni, Y., Hughes, J.M. and Mariano, A.N. (1995) Crystal chemistry of the monazite and xenotime structures. American Mineralogist, 80, 2126.CrossRefGoogle Scholar
Pezzotta, F., Diella, V. and Guastoni, A. (1999) Chemical and paragenetic data on gadolinite-group minerals from Baveno and Cuasso al Monte, southern Alps, Italy. America. Mineralogist, 84, 782789 CrossRefGoogle Scholar
Pezzotta, F., Diella V. and Guastoni, A. (2005) Scandium silicates from Baveno and Cuasso al Monte NYF-granites, Southern Alps (Italy). Mineralogy and genetic inferences. America. Mineralogist, 90, 14421452 CrossRefGoogle Scholar
Pinarelli, L., Del Moro, A. and Boriani, A. (1988) Rb-Sr Geochronology of Lower Permian plutonism in Massiccio dei Laghi, Southern Alps (NW Italy). Rendiconti Societá Italiana di Mineralogi. Petrologia, 43, 411428 Google Scholar
Pinarelli, L., Del Moro, A., Boriani, A. and Caironi, V. (2002) Sr, Nd isotope evidence for an enriched mantle component in the origins of the Hercynian gabbro-granite series of the ‘‘Serie dei Laghi’’ (Southern Alps, NW Italy). Europea. Journal of Mineralogy, 14, 403415 CrossRefGoogle Scholar
Pouchou, J.L. and Pichoir, F. (1985) ‘PAP’ j(rZ) procedure for improved quantitative microanalysis. Pp. 104-106 in: Microbeam Analysis (J.T. Armstrong, editor). San Francisco Press, San Francisco, California.USA.Google Scholar
Raade, G., Bernhard, F. and Ottolini, L. (2004) Replacement textures involving four scandium silicate minerals in the Heftetjern granitic pegmatite, Norway. Europea. Journal of Mineralogy, 16, 945950 CrossRefGoogle Scholar
Schaltegger, U. and Brack, P. (2007) Crustal-scale magmatic systems during intracontinental strike-slip tectonics: U, Pb and Hf isotopic constraints from Permian magmatic rocks of the Southern Alps. International Journal of Eart. Sciences, 96, 11311151 Google Scholar
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Act Crystallographica, A32, 751767 CrossRefGoogle Scholar
Stille, P. and Buletti, M. (1987) Nd-Sr isotopic characteristics of the Lugano volcanic rocks and constraints on the continental crust formation in the South Alpine domain (N. Italy-Switzerland). Contributions to Mineralogy an. Petrology, 96, 140150 Google Scholar
Ushakov, S.V., Helean, K.B., Navrotsky, A. and Boatner, L.A. (2001) Thermochemistry of rare-earth orthophosphates. Journal of Material. Research, 16, 26232633 Google Scholar
Wood, S.A. (1990) The aqueous geochemistry of the rare-earth elements and yttrium 2. Theoretical predictions of speciation in hydrothermal solutions to 350ºC at saturation water vapour pressure. Chemical Geology, 88, 99125 CrossRefGoogle Scholar