Chemical composition and species attribution of tourmalines from a rare-metal pegmatite vein with scapolite (Sangilene Highlands, Tuva)

Autor(en)
L.G. Kuznetsova, A.A. Zolotarev, O.V. Frank-Kamenetskaya, I.V. Rozhdestvenskaya, Yu.M. Bronzova, J. Spratt, Andreas Ertl
Abstrakt

Detail study of chem. compn. and regularities in isomorphic replacement in tourmalines from the scapolite-bearing rare-metal pegmatite body in basin of the Solbelder River has shown that these tourmalines are calcium ones, and their species belonging is detd. by occupation of the Y octahedral position. Compn. of the yellow tourmaline, most widespread in central parts of pegmatite body, is rather const. for characterizing by the ideal formula Ca(Mg2Li)Al6(Si6O18)(BO3)3(OH)3F. Variations in chem. compn. of zonal tourmaline crystals from the endocontact part of the pegmatite body testify to sharp change of chem. media during their formation process. Central - yellow zones of these crystals are close by compn. to tourmaline in central part of the body, but then there is sharp decrease of the Mg content: Mg2+ Fe2+, 2Mg2+ Li+ + Al3+ and Mg2+ + OH- Al3+ + O2-. Compn. of dark-green edge parts of tourmalines may be characterized by the ideal formula Ca(Al1.5Li1.5)Al6(Si6O18)(BO3)3(OH2O)(F). Obtained results indicate the specific conditions of the pegmatite-forming. Crystal-chem. formulas of studied tourmalines, confirmed by structural data, allow to consider them as the new species in the tourmalines group.

Organisation(en)
Institut für Mineralogie und Kristallographie
Externe Organisation(en)
Russian Academy of Sciences, Saint Petersburg State University, Natural History Museum London
Journal
Proceedings of the Russian Mineralogical Society
Band
140
Seiten
102-116
Anzahl der Seiten
15
ISSN
0869-6055
Publikationsdatum
2011
Peer-reviewed
Ja
ÖFOS 2012
105116 Mineralogie
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/cc326a58-87da-4f50-8b40-2dee8d4a0268