Hostname: page-component-7f64f4797f-fz5kh Total loading time: 0 Render date: 2025-11-04T00:40:47.759Z Has data issue: false hasContentIssue false
  • English
  • Français

Octahedrally coordinated vacancies in tourmaline: a theoretical approach

Published online by Cambridge University Press:  05 July 2018

F. Bosi
F. Bosi*
Affiliation:
Dipartimento di Scienze della Terra, Sapienza Università di Roma, P.le A. Moro, 5, I-00185 Rome, Italy
*
E-mail: ferdinando.bosi@uniroma1.it
Get access Rights & Permissions [Opens in a new window]

Abstract

Bond-valence theory is used to explore the local arrangements involving vacancies at the Y and Z sites in the tourmaline structure. The local bond-valence requirements of all possible local arrangements around the O8, O7, O6, O3 and O1 anion-sites have been determined for Y- and Z-site vacancies locally associated with Li1+, Mg2+, Al3+, Fe2+, Fe3+, B3+ and Si4+. The results show that arrangements involving tetrahedrally coordinated TR3+-cations and octahedrally coordinated YR2+- and ZR2+-cations around O8, 07 and O6 can be ruled out, together with arrangements involving vacancies and YLi1+. As the occurrence of a Y-site vacancy (Y☐) is more in accord with the valence-sum rule than the occurrence of a Z-site vacancy (Z☐), Y☐ is more likely to occur than Z☐ in tourmaline. Local arrangements involving vacancies around O1- and O3-sites can be stable for OH−, but not for O2−. Of particular interest in this regard are the arrangements [YR3+YR3+Y☐]−O1(OH−) and [ZR3+ZR3+Y☐]−O3(OH−), which yield the smallest deviations from the valence-sum rule. Coupling these stable arrangements with 2 × [TSi4+ZR3+ Y☐]−O6(O2−) forms larger vacancy clusters: [Y(R3+)2−O1(OH−)−y(☐)− O3(OH−)−O6(O2−)2−(ZR3+ TSi4+)2]. In tourmaline, vacancies are more favoured to occur at Y rather than at Z, in tandem with OH− at O3 and O1, R3+ at Y and Z and Si4+ at T.

Keywords

tourmalinebond-valence theorylocal arrangementvacancystability

Information

Type
Research Article
Information
Mineralogical Magazine , Volume 74 , Issue 6 , December 2010 , pp. 1037 - 1044
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Agrosì, G., Bosi, F., Lucchesi, S., Melchiorre, G. and Scandale, E. (2006) Mn-tourmaline crystals from island of Elba (Italy) growth history and growth marks. American Mineralogist, 91, 944–952.CrossRefGoogle Scholar
Andreozzi, G.B., Bosi, F. and Longo, M. (2008) Linking Mössbauer and structural parameters in elbaite-schorl-dravite tourmalines. American Mineralogist, 93, 658–666.CrossRefGoogle Scholar
Bloodaxe, E.S., Hughes, J.M., Dyar, M.D., Grew, E.S. and Guidotti, C.V. (1999) Linking structure and chemistry in the schorl-dravite series. American Mineralogist, 84, 922–928.CrossRefGoogle Scholar
Bosi, F. (2008) Disordering of Fe2+ over octahedrally coordinated sites of tourmaline. American Mineralogist, 93, 1647–1653.CrossRefGoogle Scholar
Bosi, F. (2011) Stereochemical constraints in tourma-line: from short-range to long-range structure. The Canadian Mineralogist, 48, in press.CrossRefGoogle Scholar
Bosi, F. and Lucchesi, S. (2004) Crystal chemistry of the schorl-dravite series. European Journal of Mineralogy, 16, 335–344.CrossRefGoogle Scholar
Bosi, F. and Lucchesi, S. (2007) Crystal chemical relationships in the tourmaline group: structural constraints on chemical variability. American Mineralogist, 92, 1050–1063.Google Scholar
Bosi, F., Lucchesi, S. and Reznitskii, L. (2004) Crystal chemistry of the dravite-chromdravite series. European Journal of Mineralogy, 16, 345–352.CrossRefGoogle Scholar
Bosi, F., Agrosi, G., Lucchesi, S., Melchiorre, G. and Scandale, E. (2005a) Mn-tourmaline from island of Elba (Italy). Crystal chemistry. American Mineralogist, 90, 1661–1668.CrossRefGoogle Scholar
Bosi, F., Andreozzi, G.B., Federico, M., Graziani, G. and Lucchesi, S. (2005b) Crystal chemistry of the elbaite-schorl series. American Mineralogist, 90, 1784–1792.CrossRefGoogle Scholar
Bosi, F., Balić-Žunić, T. and Surour, A.A. (2010) Crystal structure analysis of four tourmalines from the Cleopatra's Mines (Egypt) and Jabal Zalm (Saudi Arabia), and the role of Al in the tourmaline group. American Mineralogist, 95, 510–518.CrossRefGoogle Scholar
Burt, D.M. (1989) Vector representation of tourmaline compositions. American Mineralogist, 74, 826–839.Google Scholar
Brown, I.D. (2002) The chemical bond in inorganic chemistry: the bond valence model. Series: International Union of Crystallography Monographs on Crystallography, 12, Oxford University Press, 288 pp.Google Scholar
Brown, I.D. and Altermatt, D. (1985) Bond-valence parameters obtained from a systematic analysis of the Inorganic Crystal Structure Database. Ada Crystallographica, B41, 244-247.CrossRefGoogle Scholar
Foit, F.F. and Rosenberg, P.E. (1977) Coupled substitutions in the tourmaline group. Contributions to Mineralogy and Petrology, 62, 109–127.CrossRefGoogle Scholar
Hawthorne, F.C. (1996) Structural mechanisms for light element variations in tourmaline. The Canadian Mineralogist, 34, 123–132.Google Scholar
Hawthorne, F.C. (1997) Short-range order in amphiboles: a bond-valence approach. The Canadian Mineralogist, 35, 203–218.Google Scholar
Hawthorne, F.C. (2002) Bond valence constraints on the chemical composition of tourmaline. The Canadian Mineralogist, 40, 789–797.CrossRefGoogle Scholar
Hawthorne, F.C., Della Ventura, G., Oberti, R., Robert, J.L., and Iezzi, G. (2005) Short-range order in minerals: amphiboles. The Canadian Mineralogist, 43, 1895–1920.CrossRefGoogle Scholar
Henry, D.J. and Dutrow, B.L. (1996) Metamorphic tourmaline and its petrogenetic applications. Pp. 503—557 in: Boron: Mineralogy, Petrology and Geochemistry (E.E. Grew and L.M. Anovitz, editors). Reviews in Mineralogy, 33, Mineralogical Society of America, Washington, D.C.CrossRefGoogle Scholar
Hughes, J.M., Ertl, A., Dyar, M.D., Grew, E.S., Wiedenbeck, M. and Brandstatter, F. (2004) Structural and chemical response to varying [4]B content in zoned Fe-bearing olenite from Koralpe, Austria. American Mineralogist, 49, 447–454.CrossRefGoogle Scholar
Lussier, A.J., Aguiar, P.M., Michaelis, V.K., Kroeker, S., Herwig, S., Abdu, Y. and Hawthorne, F.C. (2008) Mushroom elbaite from the Kat Chay mine, Momeik, near Mogok, Myanmar: I. Crystal chemistry by SREF, EMPA, MAS NMR and Mossbauer spectroscopy. Mineralogical Magazine, 72, 747–761.CrossRefGoogle Scholar
Lussier, A.J., Hawthorne, F.C., Aguiar, P.M., Michaelis, V.K. and Kroeker, S. (2009) The occurrence of tetrahedrally coordinated Al and B in tourmaline: a 11B and 27Al MAS NMR study. American Mineralogist, 94, 785–792.CrossRefGoogle Scholar
Novák, M., Selway, L. Černý, P., Hawthorne, F.C. and Ottolini, L. (1999) Tourmaline of the elbaite-dravite series from an elbaite-subtype pegmatite at Blizná, southern Bohemia, Czech Republic. European Journal of Mineralogy, 11, 557–568.CrossRefGoogle Scholar
Novák, M., Povondra, P. and Selway, J.B. (2004) Schorl—oxy-schorl to dravite—oxy-dravite tourmaline from granitic pegmatites; examples from the Moldanubicum, Czech Republic. European Journal of Mineralogy, 16, 323–333.Google Scholar
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Ada Crystallographica, A32, 751-767.CrossRefGoogle Scholar