Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-20T00:28:41.277Z Has data issue: false hasContentIssue false
  • English
  • Français

The crystal chemistry of holtite

Published online by Cambridge University Press:  05 July 2018

L. A. Groat ,
E. S. Grew ,
R. J. Evans ,
A. Pieczka  and
T. S. Ercit
L. A. Groat*
Affiliation:
Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada
E. S. Grew
Affiliation:
Department of Earth Sciences, University of Maine, 5790 Bryand Global Sciences Center, Orono, Maine 04469-5790, USA
R. J. Evans
Affiliation:
Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia V6T 1Z4, Canada
A. Pieczka
Affiliation:
Department of Mineralogy, Petrography, and Geochemistry, AGH-University of Science and Technology, Mickiewicza 30, 30-059 Kraków, Poland
T. S. Ercit
Affiliation:
Canadian Museum of Nature, Research Division, Ottawa, Ontario KIP 6P4, Canada
*
* E-mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

Holtite, approximately (Al,Ta,□)Al6(BO3)(Si,Sb3+,As3+)Σ3O12(O,OH,□s)Σ3, is a member of the dumortierite group that has been found in pegmatite, or alluvial deposits derived from pegmatite, at three localities: Greenbushes, Western Australia; Voron'i Tundry, Kola Peninsula, Russia; and Szklary. Lower Silesia, Poland. Holtite can contain >30 wt.% Sb2O3, As2O3, Ta2O5, Nb2O5, and TiO2 (taken together), but none of these constituents is dominant at a crystallographic site, which raises the question whether this mineral is distinct from dumortierite. The crystal structures of four samples from the three localities have been refined to R1 = 0.02—0.05. The results show dominantly: Al, Ta, and vacancies at the Al(l) position; Al and vacancies at the Al(2), (3) and (4) sites; Si and vacancies at the Si positions; and Sb, As and vacancies at the Sb sites for both Sb-poor (holtite I) and Sb-rich (holtite II) specimens. Although charge-balance calculations based on our single-crystal structure refinements suggest that essentially no water is present, Fourier transform infrared spectra confirm that some OH is present in the three samples that could be measured. By analogy with dumortierite, the largest peak at 3505-3490 cm-1 is identified with OH at the O(2) and O(7) positions. The single-crystal X-ray refinements and FTIR results suggest the following general formula for holtite: Al7-[5x+y+z]/3 (Ta,Nb)x□[2x+y+z]\3,BSi3-y(Sb,As)yO18-y-z(OH)z, where x is the total number of pentavalent cations, y is the total amount of Sb + As, and z ⩽ y is the total amount of OH. Comparison with the electron microprobe compositions suggests the following approximate general formulae Al5.83(Ta,Nb)0.50□0.67BSi2.50(Sb,As)0.50O17.00(OH)0.50 and Al5.92(Ta,Nb)0.25□0.83BSi2.00(Sb,As)1.00O16.00(OH)1.00 for holtite I and holtite II respectively. However, the crystal structure refinements do not indicate a fundamental difference in cation ordering that might serve as a criterion for recognizing the two holtites as distinct species, and anion compositions are also not sufficiently different. Moreover, available analyses suggest the possibility of a continuum in the Si/(Sb + As) ratio between holtite I and dumortierite, and at least a partial continuum between holtite I and holtite II. We recommend that use of the terms holtite I and holtite II be discontinued.

Keywords

holtitedumortieritecrystal chemistrydiscontinuedWestern AustraliaKola PeninsulaLower Silesia
Type
Research Article
Information
Mineralogical Magazine , Volume 73 , Issue 6 , December 2009 , pp. 1033 - 1050
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2009

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.)

References

Alexander, V.D., Griffen, D.T. and Martin, TJ. (1986) Crystal chemistry of some Fe- and Ti-poor dumortierites. American Mineralogist, 71, 786–794.Google Scholar
Armstrong, J.T. (1995) CITZAF: A package of correction programs for the quantitative electron microbeam X-ray analysis of thick polished materials, thin films, and particles. Microbeam Analysis, 4, 177–200.Google Scholar
Borghi, A., Cossio, R., Fiora, L., Olmi, F. and Vaggelli, G. (2004) Chemical determination of coloured zoned minerals in ‘natural stones’ by EDS/WDS electron microprobe: an example from dumortierite quartz-ites. X-ray Spectrometry, 33, 21–27.CrossRefGoogle Scholar
Cempirek, J. and Novak, M. (2005) A green dumortierite from Kutna Hora, Moldanubicum, Czech Republic: spectroscopic and structural study. Pp. 4—5 in: International Meeting Crystallization Processes in Granitic Pegmatites (Pezzotta, F., editor). Elba, Italy. 2005, Book of Abstracts.Google Scholar
Creagh, D.C. and Hubbell, J.H. (1992) International Tables for Crystallography, Vol C. Kluwer Academic Publishers, Boston, USA, 200–206.Google Scholar
Creagh, D.C. and McAuley, W.J. (1992) International Tables for Crystallography, Vol C. Kluwer Academic Publishers, Boston, USA, 219–222.Google Scholar
Cromer, D.T. and Waber, J.T. (1974) International Tables for X-ray Crystallography, Vol. IV. The Kynoch Press, Birmingham, UK.Google Scholar
Ferraris, G., Ivaldi, G. and Chopin, C. (1995) Magnesiodumortierite, a new mineral from very-high-pressure rocks (Western Alps). Part I: Crystal structure. European Journal of Mineralogy, 7, 167–174.CrossRefGoogle Scholar
Fuchs, Y., Ertl, A., Hughes, J.M., Prowatke, S., Brandstatter, F. and Schuster, R. (2005) Dumortierite from the Gfohl unit: Lower Austria; chemistry, structure, and infra-red spectroscopy. European Journal of Mineralogy, 17, 173–183.CrossRefGoogle Scholar
Golovastikov, N.I. (1965) The crystal structure of dumortierite. Soviet Physics Doklady, 10, 493–495.Google Scholar
Grew, E.S. (1996) Borosilicates (exclusive of tourma-line) and boron in rock-forming minerals in metamorphic environments. Pp. 387—502. in: Boron: Mineralogy, Petrology, and Geochemistry. (Grew, E. S. and Anovitz, L. M., editors). Reviews in Mineralogy, 33, Mineralogical Society of America, Chantilly, Virginia. USA.Google Scholar
Grew, E.S., Graetsch, H., Poter, B., Yates, M.G., Buick, I., Bernhardt, H.-J., Schreyer, W, Werding, G, Carson, C.J. and Clarke, G.L. (2008) Boralsilite, Ali6B6Si2O37, and ‘boron-mullite': compositional variations and associated phases in experiment and nature. American Mineralogist, 93, 283–299.CrossRefGoogle Scholar
Groat, L.A., Grew, E.S., Ercit, T.S. and Piezcka, A. (2001) The crystal chemistry of dumortierite and holtite, aluminoborosilicates with heavy elements. Geological Society of America Abstracts with Programs, 33, Abstract 383.Google Scholar
Groat, L.A., Grew, E.S., Ercit, T.S. and Pieczka, A. (2002) The crystal chemistry of holtite. Abstracts of the 18th General Meeting of the International Mineralogical Association, p. 209. Hatert, F. and Burke, E.A.J. (2008) The MA-CNMNC dominant-constituent rule revisited and extended. The Canadian Mineralogist, 46, 717–728.Google Scholar
Hoskins, B.F., Mumme, W.G. and Pryce, M.W. (1989) Holtite, (Si2.25Sbo.75)B[(Al6(Alo.43Tao.27no.3o) O15(O,OH)2.25]: crystal structure and crystal chemistry. Mineralogical Magazine, 53, 457–463.CrossRefGoogle Scholar
Ibers, J.A. and Hamilton, W.C. (1964) Dispersion corrections and crystal structure refinements. Ada Crystallographica, 17, 781–782.CrossRefGoogle Scholar
Kazantsev, S.S., Pushcharovsky, D.Yu., Pasero, M., Merlino, S., Zubkova, N.V., Kabalov, Yu.K. and Voloshin, A.V. (2005) Crystal structure of holtite I. Crystallography Reports, 50, 42–47.CrossRefGoogle Scholar
Kazantsev, S.S., Zubkova, N.V. and Voloshin, A.V. (2006) Refinement of composition and structure of holtite I. Crystallography Reports, 51, 412–413.CrossRefGoogle Scholar
Locock, A.J., Piilonen, P.C., Ercit, T.S. and Rowe, R. (2006) New mineral names. American Mineralogist, 91, 216–224.CrossRefGoogle Scholar
Moore, P.B. and Araki, T. (1978) Dumortierite, Si3B[Al675o.250i7 25(OH)o.75]: a detailed structure analysis. Neues Jahrbuch fiir Mineralogie Abhandlungen, 132, 231–241.Google Scholar
Pekov, I.V. (1998) Minerals first discovered on the territory of the former Soviet Union. Ocean Pictures, Moscow.Google Scholar
Pieczka, A. and Marszalek, M. (1996) Holtite - the first occurrence in Poland. Mineralogia Polonica, 27, 3–8.Google Scholar
Platonov, A.N., Langer, K., Chopin, C., Andrut, M. and Taran, M.N. (2000) Fe2+-Ti4+ charge-transfer in dumortierite. European Journal of Mineralogy, 12, 521–528.CrossRefGoogle Scholar
Pouchou, J.L. and Pichoir, F. (1985) “PAP” ϕ(ρZ) procedure for improved quantitative microanalysis. Microbeam Analysis, 104—106.Google Scholar
Povarennykh, A.S. (1978) The use of infrared spectra for the determination of minerals. American Mineralogist, 63, 956–959.Google Scholar
Pryce, M.W. (1971) Holtite: a new mineral allied to dumortierite. Mineralogical Magazine, 38, 21–25.CrossRefGoogle Scholar
Pryce, M.W. and Chester, J. (1978) Minerals of the Greenbushes Tinfield. Mineralogical Record, 9, 81–84.Google Scholar
Rossman, G.R. (1988) Vibrational spectroscopy of hydrous components. Pp. 193—206. in: Spectroscopic Methods in Mineralogy and Geology. (Hawthorne, F. C., editor). Reviews in Mineralogy, 18, Mineralogical Society of America, Chantilly, Virginia. USA.Google Scholar
Vaggelli, G., Olmi, F., Massi, M., Giuntini, L., Fedi, M., Fiora, L., Cossio, R. and Borghi, A. (2004) Chemical investigation of coloured minerals in natural stones of commercial interest. Microchimica Ada, 145, 249–254.Google Scholar
Voloshin, A.V. and Pakhomovskiy, Ya.A. (1988) Mineralogy of Tantalum and Niobium in Rare-Metal Pegmatites. Nauka, Leningrad (in Russian).Google Scholar
Voloshin, A.V., Gordienko, V.V., Gel'man, Ye.M., Zorina, MX., Yelina, N.A., Kul'chitskaya, Ya.A., Men'shikov, Yu.P., Polezhayeva, L.I., Ryzhova, R.I., Sokolov, P.B. and Utochkina, G.I. (1977) Holtite (first find in the USSR) and its relationship with other tantalum minerals in rare-metal pegmatites. Novyye Mineraly i Pervyye Nakhodki v SSSR, 106(3), 337–347 (in Russian).Google Scholar
Voloshin, A.V., Pakhomovskiy, Ya.A. and Zalkind, O.A. (1987) An investigation of the chemical composition and IR-spectroscopy of holtite. in: Mineral ‘nyye Assotsiatsii i Mineraly Magmaticheskikh Kompleksov Kol'skogo Polyostrova, Apatity, Kol'skiy Filial AN SSSR, 14—34 (in Russian).Google Scholar
Werding, G. and Schreyer, W. (1990) Synthetic dumortierite: its PTX-dependent compositional variations in the system Al2O3-B2O3-SiO2-H2O. Contributions to Mineralogy and Petrology, 105, 11–24.CrossRefGoogle Scholar
Zubkova, N.V., Pushcharovskii, D.Yu., Yu.K, Kabalov, Kazantsev, S.S. and Voloshin, A.V. (2006) Crystal structure of holtite II. Crystallography Reports, 51, 16–22.CrossRefGoogle Scholar
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 1

Download Groat et al. supplementary material(File)
File 166.9 KB
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 2

Download Groat et al. supplementary material(File)
File 112.1 KB
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 3

Download Groat et al. supplementary material(File)
File 23.6 KB
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 4

Download Groat et al. supplementary material(File)
File 24 KB
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 5

Download Groat et al. supplementary material(File)
File 24 KB
Supplementary material: File

Groat et al. supplementary material

Supplementary Data 6

Download Groat et al. supplementary material(File)
File 23.4 KB