Skip to main content Accessibility help
×
Home

Th-rich loparite from the Khibina alkaline complex, Kola Peninsula: isomorphism and paragenesis

  • Roger H. Mitchell (a1) and Anton R. Chakhmouradian (a1)

Abstract

Th-rich (up to 18.4 wt% ThO2) loparite occurs as an accessory phase in foyaite pegmatites at Mt. Eveslogchorr, Khibina complex, Russia. It is associated with aegirine, astrophyllite, eudialyte, lorenzenite, lamprophyllite, magnesio-arfvedsonite and gerasimovskite. Loparite crystals are zoned from niobian loparite (core) to niobian thorian and thorian niobian loparite (rim). Th-enrichment is accompanied by a decrease in Na, LREE, Sr and increase in A-site vacancies. The most Th-rich composition approaches (Na0.39 LREE 0.19Th0.12Ca0.05Sr0.02)Σ0.77(Ti0.76Nb0.27)Σ1.03O3. The mineral is partly or completely metamict and after annealing gives an X-ray diffraction powder pattern similar to that of synthetic NaLaTi2O6 and naturally occurring loparite of different composition. For the Th-rich rim sample, the five strongest diffraction lines (Å) are: 2.72 (100) 110, 1.575 (60) 211, 1.925 (40), 1.368 (30) 220, 1.222 (20) 310; a = 3.867(2) Å. The X-ray diffraction patterns do not exhibit peak splitting or other diffraction lines typical of low-symmetry and ordered perovskite-type structures. Composition determinations, infrared transmission spectroscopy and X-ray diffractometry show that thorian loparite is partly replaced by betafite with LREE and Th as dominant A-site cations (‘ceriobetafite’). Some loparite samples also exhibit thin replacement mantles of belyankinite with high LREE 2O3 and ThO2 contents. Both ‘ceriobetafite’ and belyankinite were formed due to metasomatic alteration of loparite.

Copyright

References

Hide All
Balić Žunić, T., Šćavničar, S and Grobenski, Z. (1984) The structure of thorium (IV) dititanium (IV) oxide, ThTi2O6 . Croat. Chem. Acta, 57, 645–51.
Belous, A.G., Novitskaya, G.N., Gavrilova, L.G., Polyanetskaya, S.V. and Makarova, Z.Ya. (1985) Lanthanum titanate-zirconates with the perovskite structure. Sov. Prog. Chem., 51, 1315.
Borodin, L.S. (1954) On accommodation of water in the crystal lattice of perovskite-group minerals. Doklady AN SSSR, 95, (in Russian), 873–5.
Borodin, L.S. and Kazakova, M.E. (1954) Irinite – a new mineral from the perovskite group. Doklady AN SSSR, 97, (in Russian), 725–8.
Chakhmouradian, A.R. and Mitchell, R.H. (1997) Compositional variation of perovskite-group minerals from the carbonatite complexes of the Kola Alkaline Province,, Russia. Canad. Mineral., 35, 1293–310.
Chakhmouradian, A.R. and Mitchell, R.H. (1998) Compositional variation of perovskite-group minerals from the Khibina alkaline complex, Kola Peninsula. Canad. Mineral., 36, (in press).
Filatov, S.K. and Frank-Kamenetskii, V.A. (1969) Structural characteristics of cubic ZrO2 stabilized by calcium. Sov. Phys. Cryst., 14, 414–5.
Galakhov, A.V. (1975) The petrology of the Khibina Alkaline Massif. Nauka Press, Leningrad, (in Russian), 256 pp.
Gerasimovskii, V.I. and Kazakova, M.E. (1950) Belyankinite – a new mineral. Doklady AN SSSR, 71, (in Russian), 925–7.
Grunin, V.S., Razumenko, M.V., Patrina, I.V., Filatov, S.K. and Alekseyeva, T.V. (1983) Mode of existence and abundance of TiO2-rutile, anatase and brookite. Doklady Earth Sci. Sect., 268, 149–50.
Haggerty, S.E. and Mariano, A.N. (1983) Strontianloparite and strontio-chevkinite: two new minerals in rheomorphic fenites from the Parana Basin carbonatites, South America. Contrib. Mineral. Petrol., 84, 365–81.
Hogarth, D.D. (1961) A study of pyrochlore and betafite. Canad. Mineral., 6, 610–33.
Hogarth, D.D. (1989) Pyrochlore, apatite and amphibole: distinctive minerals in carbonatites. In: Carbonatites (Bell, K., ed), Unwyn Hyman, London, 105–48.
Kapustin, Yu.L. (1989) Rare earth-bearing pyrochlore from peralkaline pegmatites of the Khibina massif. New data on minerals (Trudy Mineral. Muz. AN SSSR), 36, (in Russian), 155–61.
Keller, C. (1965) Die Reaktion der Dioxide der Elemente Thorium bis Americium mit Niob- und Tantalpentoxid (The reaction of dioxides of the elements from thorium to americium with niobium and tantalum pentoxides). J. Inorg. Nucl. Chem., 27, 1233–46.
Kogarko, L.N., Kononova, V.A., Orlova, M.P. and Woolley, A.R. (1995 ) Alkaline Rocks and Carbonatites of the World. Part 2: Former USSR. Chapman&Hall, London U.K., 226 pp.
Kostyleva-Labuntsova, E.E., Borutskii, B.E., Sokolova, M.N., Shliukova, Z.V., Dorfman, M.D., Dudkin, O.B., Kozyreva, L.V. and Ikorskii, S.V. (1978a) The Mineralogy of the Khibina Massif. Vol. 1. Nauka Press, Moscow, (in Russian), 228 p.
Kostyleva-Labuntsova, E.E., Borutskii, B.E., Sokolova, M.N., Shliukova, Z.V., Dorfman, M.D., Dudkin, O.B., Kozyreva, L.V. and Ikorskii, S.V. (1978b) The Mineralogy of the Khibina Massif. Vol. 2. Nauka Press, Moscow, (in Russian), 588 p.
Kovba, L.M. and Trunov, V.K. (1962) Double oxides containing tungsten, tantalum, or niobium. Doklady AN SSSR, 147, (in Russian), 622–4.
Kozyreva, L.V. (1990) Aegirine-feldspar veins in the north-eastern part of the Khibina massif. In: Alkaline Magmatism in the North-eastern Part of the Baltic Shield, Kola Sci. Centre Press, Apatity, (in Russian), 4256.
Kozyreva, L.V., Men’shikov, Yu.P. and Lednev, A.I. (1991) Loparite mineralization of the Khibina massif. In: New Data on the Rare-metal Mineralogy of the Kola Peninsula, Kola Sci. Centre Press, Apatity, (in Russian), 3744.
Krivokoneva, G.K. and Sidorenko, G.A. (1971) The essence of the metamict transformation in pyrochlores. Geochem. Int., 1971, 113–22.
Kukharenko, A.A. & Bagdasarov, E.A. (1961 ) Perovskite from ultramafic-alkaline rocks of the Kola Peninsula. Trudy VSEGEI, 45, (in Russian), 3766.
Labeau, M. and Joubert, J.C. (1978) Etude cristallochimique des phases de type perovskite du systeme Th0.25NbO3–NaNbO3 (A crystal-chemical study of perovskite-type phases of the system Th0.25NbO3–NaNbO3). J. Solid State Chem., 25, 347–53.
Lupini, L., Williams, C.T. and Woolley, A.R. (1992) Zr-rich garnet and Zr- and Th-rich perovskite from the Polino carbonatite, Italy. Mineral. Mag., 56, 581–6.
Mitchell, R.H. (1996) Perovskites: a revised classification scheme for an important rare earth element host in alkaline rocks. In: Rare Earth Minerals: Chemistry, Origin and Ore Deposits (Jones, A.P., Wall, F. and Williams, C.T., eds), Chapman & Hall, London, 4176.
Mitchell, R.H. and Chakhmouradian, A.R. (1996) Compositional variation of loparite from the Lovozero alkalin e complex, Russia. Canad. Mineral., 34, 977–90.
Mitchell, R.H. and Vladykin, N.V. (1993) Rare earth element-bearing tausonite and potassium barium titanates from the Little Murun potassic alkaline complex, Yakutia, Russia. Mineral. Mag., 57, 651–64.
Mitchell, R.H., Chakhmouradian, A.R. and Yakovenchuk, V.N. (1996) “Nioboloparite“: a reinvestigation and discreditation. Canad. Mineral., 34, 991–9.
Náray-Szabó, I. (1947) The perovskite-structure family. Muegyet. Közlem., 1947, 3041.
Nyquist, R.A. and Kagel, R.O. (1971) Infrared Spectra of Inorganic Compounds (3800–45 cm−1). Academic Press, New York, 495 pp.
Parker, R.L. and Sharp, W.N. (1970) Mafic-ultramafic igneous rocks and associated carbonatites of the Gem Park Complex, Custer and Fremont Counties, Colorado. US Geol. Surv. Prof. Paper, 649, 24 p.
Pilipenko, A.T., Shevchenko, L.L. and Patseliuk, V.A. (1971) Infrared spectra of some niobium minerals. Zh. Prikl. Spektr. (J. Appl. Spectr. ), 14, (in Russian), 638–43.
Ruh, R. and Wadsley, A.D. (1966) The crystal structure of ThTi2O6 (brannerite). Acta Cryst., 21, 974–8.
Semenov, E.I. (1957) Oxides and hydroxides of titanium and niobium in the Lovozero alkaline massif. Trudy IMGRE, 1, (in Russian), 4159. Abstracted in Amer. Mineral. (1958), 43, 1220–1.
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Cryst., A32, 751–67.
Shilin, L.L., Burova, T.A. and Dmitrieva, M.T. (1966) Accessory pyrochlore in pegmatites of the Khibiny Tundra. In: Alkaline Rocks of the Kola Peninsula, Kola Sci. Centre Press, Apatity, (in Russian), 93–8.
Smirnova, N.L. and Belov, N.V. (1969) Isomorphism and related concepts in the light of crystal chemistry. Geokhim., 1969, (in Russian), 1291–301.
Smith, A.J. and Welch, A.J.E. (1960) Some mixed metal oxides of perovskite structure. Acta Cryst., 13, 653–6.
Sniatkova, O.L., Proniagin, N.I., Markitakhina, T.M. and Efstaf’ev, A.S. (1986) New data on the structural position of urtite-ijolite-melteigites in nepheline syenites of the Khibina massif. In: Deposits of Non-metallic Mineral Resources in the Kola Peninsula, Kola Sci. Centre Press, Apatity, (in Russian), 1117.
Sych, A.M., Belokon’, A.T., Dem’yanenko, V.P. and Eremenko, L.A. (1973) Vibration spectra of perovskite-structure rare-earth niobates. Ukrain. Phys. Zh. (Ukrain. J. Phys.), 18, (in Russian), 787–92.
Tikhonenkova, R.P., Kazakova, M.E. and Kataeva, Z.T. (1982) Chemistry of accessory loparite from alkaline rocks and its genetic significance. In: Accessory Minerals of Magmatic and Metamorphic Rocks, Nauka Press, Moscow, (in Russian), 150–61.
Trunov, V.K. and Kovba, L.M. (1963) X-ray analysis of thorium tungstate and molybdenate. Vest. Mosk. Univ., Ser. II Khim., 18, (in Russian), 60–3.
Vidyasagar, K. and Gopalakrishnan, J. (1982) New vanadium oxides with perovskite type structure: AThV2O6 (A = Ca, Sr). Indian J. Chem., 21A, 716–7.
Vlasov, K.A., Kuz’menko, M.Z. and Es’kova, E.M. (1966) The Lovozero Alkaline Massif. Oliver & Boyd Ltd., Edinburgh, U.K., 627 pp.
Voloshin, A.V., Pakhomovskii, Ya.A., Pushcharovskii, D.Yu., Nadezhina, T.N., Bakhchisaraitsev, A.Yu. and Kobiashev, Yu.S. (1989) Strontian pyrochlore: Composition and structure. New data on minerals (Trudy Mineral. Muz. AN SSSR), 36, (in Russian), 1224.
Zak, S.I., Kamenev, E.A., Minakov, F.V., Armand, A.L., Mikheichev, A.S. and Petersil’e, I.A. (1972) The Khibina Alkaline Massif. Nedra Press, Leningrad, (in Russian), 175 pp.
Zhu, W.J. and Hor, H.P. (1995) A new titanium perovskite oxide, Na2/3Th1/3TiO3 . J. Solid State Chem., 120, 208–9.

Keywords

Th-rich loparite from the Khibina alkaline complex, Kola Peninsula: isomorphism and paragenesis

  • Roger H. Mitchell (a1) and Anton R. Chakhmouradian (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.