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Gem amphiboles from Mogok, Myanmar: crystal-structure refinement, infrared spectroscopy and short-range order–disorder in gem pargasite and fluoro-pargasite

Published online by Cambridge University Press:  14 September 2018

Maxwell C. Day
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
Frank C. Hawthorne*
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
Umberto Susta
Affiliation:
Dipartimento di Scienze, Università di Roma Tre, Largo S. Leonardo Murialdo 1, 00146 Rome, Italy
Giancarlo Della Ventura
Affiliation:
Dipartimento di Scienze, Università di Roma Tre, Largo S. Leonardo Murialdo 1, 00146 Rome, Italy
George E. Harlow
Affiliation:
Department of Earth and Planetary Sciences, American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024-5192, USA
*
*Author for correspondence: Frank C. Hawthorne, Email: [email protected]

Abstract

The crystal structures of six gem-quality pargasites and fluoro-pargasites from Mogok, Myanmar, space group C2/m, Z = 2, have been refined to R1 indices of 2.20–2.90% using MoKα X-radiation. The unit formulae were calculated from the results of electron-microprobe analysis, and were used with the refined site-scattering values and the observed mean bond lengths to assign site populations. TAl occurs at both the T(1) and T(2) sites but is strongly ordered at T(1). [6]Al is partly disordered over the M(2) and M(3) sites but does not occur at the M(1) site. ANa is split between the A(2) and A(m) sites and K occurs at the A(m) site. The infrared spectra in the principal OH-stretching region were measured and the fine structure was fit to component bands. The component bands were assigned to short-range ion arrangements over the configuration symbol M(1)M(1)M(3)–O(3)–A–O(3):T(1)T(1) using the refined site-populations and the expected frequencies from previously assigned spectra in more simple amphibole compositions, and correspond to the local arrangements: (1) MgMgMg–OH–Na–OH:SiAl; (2) MgMgMg–OH–Na–F:SiAl; (3) MgMgAl–OH–Na–OH:SiAl and (4) MgMgAl–OH–Na–F:SiAl.

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Article
Copyright
Copyright © Mineralogical Society of Great Britain and Ireland 2018 

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Footnotes

Associate Editor: Peter Leverett

References

Abdu, Y. and Hawthorne, F.C. (2009) Crystal structure and Mössbauer spectroscopy of tschermakite from the ruby locality at Fiskenaesset, Greenland. The Canadian Mineralogist, 47, 917926.Google Scholar
Bocchio, R., Ungaretti, L. and Rossi, G. (1978) Crystal chemical study of eclogitic amphiboles from Alpe Arami, Lepontine Alps, Southern Switzerland. Rendiconti della Società Italiana di Mineralogia e Petrologia, 34, 453470.Google Scholar
Boschmann, K., Burns, P.C., Hawthorne, F.C., Raudsepp, M. and Turnock, A.C. (1994) A-site disorder in synthetic fluor-edenite, a crystal structure study. The Canadian Mineralogist, 47, 2130.Google Scholar
Chang, I.F. and Mitra, S.S. (1968) Application of a modified random-element-isodisplacement model to long-wavelength optic phonons of mixed crystals. Physical Review, 172, 924933.Google Scholar
Della Ventura, G., Robert, J.-L. and Hawthorne, F.C. (1996 a) Infrared spectroscopy of synthetic (Ni,Mg,Co)-potassium-richterite. Pp. 5563 in: Mineral Spectroscopy: A Tribute to Roger G. Burns (Dyar, M.D., McCammon, C. and Schaefer, M.W., editors). The Geochemical Society Special Publication No. 5. The Geochemical Society, Washington, DC.Google Scholar
Della Ventura, G., Robert, J.-L., Hawthorne, F.C. and Prost, R. (1996 b) Short-range disorder of Si and Ti in the tetrahedral double-chain unit of synthetic Ti-bearing potassium-richterite. American Mineralogist, 81, 5660.Google Scholar
Della Ventura, G., Robert, J.-L., Raudsepp, M., Hawthorne, F.C. and Welch, M.D. (1997) Site occupancies in synthetic monoclinic amphiboles: Rietveld structure-refinement and infrared spectroscopy of (nickel, magnesium, cobalt)-richterite. American Mineralogist, 82, 291301.Google Scholar
Della Ventura, G., Robert, J.-L. and Hawthorne, F.C. (1998 a) Characterization of OH-F short-range order in potassium-fluor-richterite by infrared spectroscopy in the OH-stretching region. The Canadian Mineralogist, 36, 181185.Google Scholar
Della Ventura, G., Robert, J.-L., Hawthorne, F.C., Raudsepp, M. and Welch, M.D. (1998 b) Contrasting patterns of [6]Al order in synthetic pargasite and Co-substituted pargasite. The Canadian Mineralogist, 36, 12371244.Google Scholar
Della Ventura, G., Hawthorne, F.C., Robert, J.-L., Delbove, F., Welch, M.F. and Raudsepp, M. (1999) Short-range order of cations in synthetic amphiboles along the richterite-pargasite join. European Journal of Mineralogy, 11, 7994.Google Scholar
Della Ventura, G., Robert, J.-L., Sergent, J., Hawthorne, F.C. and Delbove, F. (2001) Constraints on F vs. OH incorporation in synthetic [6]Al-bearing in monoclinic amphiboles. European Journal of Mineralogy, 13, 841847.Google Scholar
Della Ventura, G., Hawthorne, F.C., Robert, J.-L. and Iezzi, G. (2003) Synthesis and infrared spectroscopy of amphiboles along the tremolite-pargasite join. European Journal of Mineralogy, 15, 341347.Google Scholar
Della Ventura, G., Oberti, R., Hawthorne, F.C. and Bellatreccia, F. (2007) FTIR spectroscopy of Ti-rich pargasites from Lherz and the detection of O2B at the anionic O3 site in amphiboles. American Mineralogist, 92, 16451651.Google Scholar
Della Ventura, G., Bellatreccia, F., Cámara, F. and Oberti, R. (2014) Crystal-chemistry and short-range order of fluoroedenite and fluoro-pargasite: a combined X-ray diffraction and FTIR spectroscopic approach. Mineralogical Magazine, 78, 293310.Google Scholar
Gottschalk, M., Andrut, M. and Melzer, S. (1999) The determination of cummingtonite content of synthetic tremolite. European Journal of Mineralogy, 11, 967982.Google Scholar
Hawthorne, F.C. (1981) Crystal chemistry of the amphiboles. Pp. 1102 in: Amphiboles and Other Hydrous Pyriboles: Mineralogy (Veblen, David R. and Ribbe, Paul H., editors). Reviews in Mineralogy, 9A. Mineralogical Society of America, Washington, DC.Google Scholar
Hawthorne, F.C. (1983 a) The crystal chemistry of the amphiboles. The Canadian Mineralogist, 21, 173480.Google Scholar
Hawthorne, F.C. (1983 b) Characterization of the average structure of natural and synthetic amphiboles. Periodico di Mineralogia, 52, 543581.Google Scholar
Hawthorne, F.C. (1983 c) Quantitative characterization of site occupancies in minerals. American Mineralogist, 68, 287306.Google Scholar
Hawthorne, F.C. (1997) Short-range order in amphiboles: a bond-valence approach. The Canadian Mineralogist, 35, 203218.Google Scholar
Hawthorne, F.C. (2016) Short-range atomic arrangements in minerals. I: The minerals of the amphibole, tourmaline and pyroxene supergroups. European Journal of Mineralogy, 28, 513536.Google Scholar
Hawthorne, F.C. and Della Ventura, G. (2007) Short-range order in amphiboles. Pp. 173222 in: Amphiboles: Crystal Chemistry, Occurrence, and Health Issues (Hawthorne, Frank C., Oberti, Roberta, Ventura, Giancarlo Della and Mottana, Annibale, editors). Reviews in Mineralogy & Geochemistry, 67. The Mineralogical Society of America and the Geochemical Society, Chantilly, Virginia, USA.Google Scholar
Hawthorne, F.C. and Grundy, H.D. (1972) Positional disorder in the A-site of clino-amphiboles. Nature, 235, 72.Google Scholar
Hawthorne, F.C. and Grundy, H.D. (1973 a) The crystal chemistry of the amphiboles. I. Refinement of the crystal structure of ferrotschermakite. Mineralogical Magazine, 39, 3648.Google Scholar
Hawthorne, F.C. and Grundy, H.D. (1973 b) The crystal chemistry of the amphiboles. II. Refinement of the crystal structure of oxykaersutite. Mineralogical Magazine, 39, 390400.Google Scholar
Hawthorne, F.C. and Grundy, H.D. (1976) The crystal chemistry of the amphiboles. IV. X-ray and neutron refinements of the crystal structure of tremolite. The Canadian Mineralogist, 14, 334345.Google Scholar
Hawthorne, F.C. and Grundy, H.D. (1977) The crystal chemistry of the amphiboles. III. Refinement of the crystal structure of a sub-silicic hastingsite. Mineralogical Magazine, 41, 4350.Google Scholar
Hawthorne, F.C. and Oberti, R. (2007) Amphiboles: crystal chemistry. pp. 154 in: Amphiboles: Crystal Chemistry, Occurrence, and Health Issues (Hawthorne, Frank C., Oberti, Roberta, Ventura, Giancarlo Della and Mottana, Annibale, editors). Reviews in Mineralogy & Geochemistry, 67. The Mineralogical Society of America and the Geochemical Society, Chantilly, Virginia, USA.Google Scholar
Hawthorne, F.C., Ungaretti, L. and Oberti, R. (1995) Site populations in minerals: terminology and presentation of results of crystal-structure refinement. The Canadian Mineralogist, 33, 907911.Google Scholar
Hawthorne, F.C., Della Ventura, G. and Robert, J.-L. (1996 a) Short-range order of (Na,K) and Al in tremolite: An infrared study. American Mineralogist, 81, 782784.Google Scholar
Hawthorne, F.C., Oberti, R. and Sardone, N. (1996 b) Sodium at the A site in clinoamphiboles: the effects of composition on patterns of order. The Canadian Mineralogist, 34, 577593.Google Scholar
Hawthorne, F.C., Della Ventura, G., Robert, J.-L., Welch, M.F., Raudsepp, M. and Jenkins, D.M. (1997) A Rietveld and infrared study of synthetic amphiboles along the potassium-richterite-tremolite join. American Mineralogist, 82, 708716.Google Scholar
Hawthorne, F.C., Welch, M.D., Della Ventura, G., Liu, S., Robert, J.-L. and Jenkins, D.M. (2000) Short-range order in synthetic aluminous tremolites: An infrared and triple-quantum MAS NMR study. American Mineralogist, 85, 17161724.Google 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, 18951920.Google Scholar
Hawthorne, F.C., Oberti, R., Harlow, G.E., Maresch, W., Martin, R.F., Schumacher, J.C. and Welch, M.D. (2012) Nomenclature of the amphibole super-group. American Mineralogist, 97, 20312048.Google Scholar
Heavysege, D., Abdu, Y. and Hawthorne, F.C. (2015) Long-range and short-range order in gem pargasite from Myanmar: Crystal structure refinements and infrared spectroscopy. The Canadian Mineralogist, 53, 497510.Google Scholar
Iezzi, G., Della Ventura, G., Hawthorne, F.C., Pedrazzi, G. and Robert, J-L. (2005) The (Mg,Fe2+) substitution in ferri-clinoholmquistite, □Li2(Mg,Fe2+)3Fe3+2Si8O22(OH)2. European Journal of Mineralogy, 17, 733740.Google Scholar
Jenkins, D.M. (1987) Synthesis and characterization of tremolite in the system H2O–CaO–MgO–SiO2. American Mineralogist, 72, 707715.Google Scholar
Jenkins, D.M., Sherriff, B.L., Cramer, J. and Xu, Z. (1997) Al, Si and Mg occupancies in tetrahedrally and octahedrally coordinated sites in synthetic aluminous tremolite. American Mineralogist, 82, 280290.Google Scholar
Leissner, L., Schlüter, J., Horn, I. and Mihailova, B. (2015) Exploring the potential of Raman spectroscopy for crystallochemical analyses of complex hydrous silicates: I. Amphiboles. American Mineralogist, 100, 26822694.Google Scholar
Najorka, J. and Gottschalk, M. (2003) Crystal chemistry of tremolite-tschermakite solid solutions. Physics and Chemistry of Minerals, 30, 108124.Google Scholar
Oberti, R., Ungaretti, L., Cannillo, E., Hawthorne, F.C. and Memmi, I. (1995 a) Temperature-dependent Al order-disorder in the tetrahedral double-chain of C2/m amphiboles. European Journal of Mineralogy, 7, 10491063.Google Scholar
Oberti, R., Hawthorne, F.C., Ungaretti, L. and Cannillo, E. (1995 b) [6]Al disorder in amphiboles from mantle peridotites. The Canadian Mineralogist, 33, 867878.Google Scholar
Oberti, R., Sardone, N., Hawthorne, F.C., Raudsepp, M. and Turnock, A.C. (1995 c) Synthesis and crystal-structure refinement of synthetic fluor-pargasite. The Canadian Mineralogist, 33, 2531.Google Scholar
Oberti, R., Hawthorne, F.C., Cámara, F. and Raudsepp, M. (1998) Synthetic fluoro-amphiboles: site preferences of Al, Ga, Sc and inductive effects on mean bond-lengths of octahedra. The Canadian Mineralogist, 36, 12451252.Google Scholar
Oberti, R., Hawthorne, F.C., Cannillo, E. and Cámara, F. (2007) Long-range order in amphiboles. Pp. 125171 in: Amphiboles: Crystal Chemistry, Occurrence, and Health Issues (Hawthorne, Frank C., Oberti, Roberta, Ventura, Giancarlo Della and Mottana, Annibale, editors). Reviews in Mineralogy & Geochemistry, 67. The Mineralogical Society of America and the Geochemical Society, Chantilly, Virginia, USA.Google Scholar
Papike, J.J., Ross, M. and Clark, J.R. (1969) Crystal-chemical characterization of clinoamphiboles based on five new structure refinements. Mineralogical Society of America Special Paper, 2, 117136.Google Scholar
Pouchou, J.L. and Pichoir, F. (1985) ‘PAP’ (φρZ) procedure for improved quantitative microanalysis. Pp. 104106 in: Microbeam Analysis (Armstrong, J.T., editor). San Francisco Press, San Francisco, California, USA.Google Scholar
Raudsepp, M., Turnock, A.C. and Hawthorne, F.C. (1987 a) Characterization of cation ordering in synthetic scandium-fluor-eckermannite, indium-fluor-eckermannite and scandium-fluor-nyböite by Rietveld structure refinement. American Mineralogist, 72, 959964.Google Scholar
Raudsepp, M., Turnock, A.C., Hawthorne, F.C., Sherriff, B.L. and Hartman, J.S. (1987 b) Characterization of synthetic pargasitic amphiboles (NaCa2Mg4M3+Si6Al2O22(OH,F)2; M3+ = Al, Cr, Ga, Sc, In) by infrared spectroscopy, Rietveld structure refinement and 27Al, 29Si, and 19F MAS NMR spectroscopy. American Mineralogist, 72, 580593.Google Scholar
Raudsepp, M., Turnock, A.C. and Hawthorne, F.C. (1991) Amphiboles synthesis at low-pressure: what grows and what doesn't. European Journal of Mineralogy, 3, 9831004.Google Scholar
Robert, J.-L., Della Ventura, G. and Thauvin, J-L. (1989) The infrared OH-stretching region of synthetic richterites in the system Na2O–K2O–CaO–MgO–SiO2–H2O–HF. European Journal of Mineralogy, 1, 203211.Google Scholar
Robert, J.-L., Della Ventura, G. and Hawthorne, F.C. (1999) Near-infrared study of short-range disorder of OH and F in monoclinic amphiboles. American Mineralogist, 84, 8691.Google Scholar
Robert, J.-L., Della Ventura, G., Welch, M.D. and Hawthorne, F.C. (2000) The OH/F substitution in synthetic pargasite at 1.5kbar, 850°C. American Mineralogist, 85, 926931.Google Scholar
Robinson, K., Gibbs, G.V., Ribbe, P.H. and Hall, M.R. (1973) Cation distributions in three hornblendes. American Journal of Science, 273A, 522535.Google Scholar
Semet, M.P. (1973) A crystal-chemical study of synthetic magnesiohastingsite. American Mineralogist, 58, 480494.Google Scholar
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallographica, A32, 751767.Google Scholar
Sheldrick, G.M. (2008) A short history of SHELX. Acta Crystallographica, A64, 112122.Google Scholar
Skogby, H. and Rossman, G.R. (1991) The intensity of amphibole OH bands in the infrared absorption spectrum. Physics and Chemistry of Minerals, 18, 6468.Google Scholar
Strens, R.G.J. (1966) Infrared study of cation ordering and clustering in some (Fe,Mg) amphibole solid solutions. Chemical Communications (Chemical Society of London), 15, 519520.Google Scholar
Tait, K.T., Hawthorne, F.C. and Della Ventura, G. (2001) Al-Mg disorder in a gem-quality pargasite from Baffin Island, Nunavut, Canada. The Canadian Mineralogist, 39, 17251732.Google Scholar
Welch, M.D. and Knight, K.S. (1999) A neutron powder diffraction study of cation ordering in high-temperature synthetic amphiboles. European Journal of Mineralogy, 11, 321331.Google Scholar
Welch, M.D., Kolodziejski, W. and Klinowski, J. (1994) A multinuclear study of synthetic pargasite. American Mineralogist, 79, 261268.Google Scholar
Welch, M.D., Liu, S. and Klinowski, J. (1998) 29Si MAS NMR systematics of calcic and sodic-calcic amphiboles. American Mineralogist, 83, 8596.Google Scholar
Wojdyr, M. (2010) Fityk: a general-purpose peak fitting program. Journal of Applied Crystallography, 43, 11261128.Google Scholar
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