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Apatite-group minerals from nepheline syenite, Pilansberg alkaline complex, South Africa

Published online by Cambridge University Press:  05 July 2018

R. P. Liferovich  and
R. H. Mitchell
R. P. Liferovich
Affiliation:
Department of Geology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, Canada P7B 5E1
R. H. Mitchell*
Affiliation:
Department of Geology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, Canada P7B 5E1
*
*E-mail: rmitchel@lakeheadu.ca
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Abstract

The nepheline syenites of the Pilansberg alkaline complex (South Africa) have undergone extensive subsolidus equilibration and alteration with a deuteric Cl- and Na-rich fluid phase. Complex assemblages of secondary minerals result from the replacement of primary alummosilicates, rinkite, eudialyte and fluorapatite. The composition of apatite group minerals formed during these alteration processes reflects the Sr- and rare earth element (REE) content, Na/Cl ratio and pH of the deuteric fluids. Apatite-group minerals are observed to have formed in the following sequence: orthomagmatic fluorapatite; strontian britholite-(Ce); strontian fluorapatite; Sr-apatite; REE-rich Sr-apatite; Sr-Na-REE- rich minerals approaching the stoichiometry of belovite-(Ce) and deloneite-(Ce); britholite-(Ce). Increasing alkalinity of the deuteric fluids is reflected by increasing amounts of Sr replacing Ca in apatite and culminates in the formation of Sr apatite containing 62.1 wt.% SrO (∼4.17 a.p.f.u. Sr). Pilansberg apatite-group minerals form a near-complete solid solution between fluorapatite and a fluorine analogue of Sr apatite with limited solution towards belovite-(Ce), Si-rich belovite-(Ce) and strontian britholite-(Ce).

Keywords

lujavritefoyaitehyperagpaiticsubsolidusalterationstrontianSr-apatitebritholite-(Ce)belovite-(Ce)Pilansberg
Type
Research Article
Information
Mineralogical Magazine , Volume 70 , Issue 5 , October 2006 , pp. 463 - 484
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2006

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References

Arden, K. M. and Halden, N. M. (1999) Crystallization and alteration history of britholite in rare-earth-element-enriched pegmatitic segregations associated with the Eden Lake complex, Manitoba, Canada. The Canadian Mineralogist, 37, 1239–1253.Google Scholar
Chakhmouradian, A. R. and Mitchell, R. H. (1999) Primary, agpaitic and deuteric stages in the evolution of accessory Sr, REE, Ba and Nb-mineralization in nepheline-syenite pegmatites at Pegmatite Peak, Bearpaw Mts., Montana. Mineralogy and Petrology, 67, 85–110.CrossRefGoogle Scholar
Chakhmouradian, A. R. and Mitchell, R. H. (2002) The mineralogy of Ba- and Zr-rich pegmatites from Gordon Butte, Crazy Mountains (Montana, USA): comparison between potassic and sodic agpaitic pegmatites. Contributions to Mineralogy and Petrology, 143, 93–114.CrossRefGoogle Scholar
Chakhmouradian, A. R., Reguir, E. P. and Mitchell, R. H. (2002) Strontium-apatite: new occurrences, and the extent of Sr-for-Ca substitution in apatite-group minerals. The Canadian Mineralogist, 40, 121–136.CrossRefGoogle Scholar
Chakhmouradian, A. R., Hughes, J. M. and Rakovan, J. (2005) Fluorcaphite, a second occurrence and detailed structural analysis: simultaneous accommodation of Ca, Sr, Na and LREE in the apatite atomic arrangement. The Canadian Mineralogist, 43, 735–746.CrossRefGoogle Scholar
Efimov, A. F., Kravchenko, S. M. and Vasil'eva, Z. V. (1962) Strontium-apatite – a new mineral. Doklady Academii Nauk USSR, Earth Science Section, 142, 113–116 (in Russian).Google Scholar
Ferguson, J. (1973) The Pilansberg alkaline province. Transactions of the Geological Society of South Africa, 376, 207–214.Google Scholar
Féménias, O., Coussaert, N., Brassinnes, S. and Demaiffe, D. (2005) Emplacement processes and cooling history of layered cyclic unit II-7 from the Lovozero alkaline massif (Kola peninsula, Russia). Lithos, 83, 371–393.CrossRefGoogle Scholar
Genkina, E. A., Malinovskii, Yu.A. and Khomyakov, A. P. (1991) Crystal structure of Sr-containing britholite. Soviet Physics Crystallography, 36, 19–22.Google Scholar
Hamilton, D. L. (1961) Nepheline as crystallization temperature indicators. Journal of Geology, 69, 321–329.CrossRefGoogle Scholar
Khomyakov, A. P. (1990) Mineralogy of hyperagpaitic alkaline rocks. Moscow, Nauka, 195 pp. (in Russian).Google Scholar
Khomyakov, A. P. (1995) Mineralogy of Hyperagpaitic Alkaline Rocks. Oxford Science, 223 pp.Google Scholar
Khomyakov, A. P., Spachenko, A. K. and Polezhaeva, L. I. (1990) Melilite and rare earth phosphate mineralization at the Namuaiv Mount (Khibina). Pp. 106–119 in: Alkaline Magmatism in the NE part of the Baltic Shield (Ivanova, T. N., Dudkin, O. B. and Arzamastsev, A. A., editors). Kola Science Centre RAS, Apatity, Russia (in Russian).Google Scholar
Khomyakov, A. P., Lisitsyn, D. V., Kulikova, I. M. and Rastsvetaeva, R. K. (1996) Deloneite-(Ce), NaCa2SrCe(PO4)3F – a new mineral with a belovite-like structure. Zapiski Vserossiiskogo Mineralogicheskogo Obshchestva, 125(5), 83–94(in Russian).Google Scholar
Khomyakov, A. P., Kulikova, I. M. and Rastsvetaeva, R. K. (1997) Fluorcaphite Ca(Sr,Na,Ca)(Ca,Sr,Ce)3(PO4)3F – a new mineral with an apatite-like structural motif. Zapiski Vserossiiskogo Mineralogicheskogo Obshchestva, 126(3), 87–97 (in Russian).Google Scholar
Kostyleva-Labuntsova, E. E., Borutsky, B. E., Sokolova, M. N., Shlyukova, Z. V., Dorfman, M. D., Dudkin, O. B. and Kozyreva, L. V. (1978) Mineralogy of Khibina Complex, part II. Nauka, Moscow, 585 pp. (in Russian).Google Scholar
Lurie, J. (1986) Mineralization of the Pilansberg Alkaline Complex. Pp. 2215–2228 in: Mineral Deposits of South Africa 2 (Anhaeusser, C. R., and Maske, S., editors). The Geological Society of South Africa, Johannesburg, South Africa.Google Scholar
Mandarino, J. A. (1999) Fleisher's Glossary of Mineral Species. The Mineralogical Record Inc., Tucson, Arizona, 225 pp.Google Scholar
Markl, G. (2001) A new type of silicate liquid immiscibility in peralkaline nepheline syenites (lujavrites) of the Ilimaussaq complex, South Greenland. Contributions to Mineralogy and Petrology, 141, 458–472.CrossRefGoogle Scholar
Markl, G. and Baumgartner, L. (2002) pH changes in peralkaline late-magmatic fluids. Contributions to Mineralogy and Petrology, 144, 331–346.CrossRefGoogle Scholar
Mitchell, R. H. and Belton, F. (2004) Niocalite-cuspidine solid solution and manganoan monticellite from natrocarbonatite, Oldoinyo Lengai, Tanzania. Mineralogical Magazine, 68, 787–799.CrossRefGoogle Scholar
Mitchell, R. H. and Liferovich, R. P. (2004) Ecandrewsite-zincian pyrophanite from lujavrite, Pilansberg alkaline complex, South Africa. The Canadian Mineralogist, 42, 1169–1178.CrossRefGoogle Scholar
Mitchell, R. H. and Liferovich, R. P. (2005) Subsolidus/ deuteric alteration of eudialyte in aegirine lujavrite, Pilansberg Alkaline Complex, South Africa. Pp. 74–76 in: Peralkaline Rocks: Sources, Economic Potential and Evolution from Alkaline Melts (Marks, M., editor). Peralk Workshop, Abstract volume, Tubingen, Germany.Google Scholar
Mitchell, R. H. and Liferovich, R. P. (2006) Subsolidus deuteric/hydrothermal alteration of eudialyte in lujavrite from the Pilansberg Alkaline Complex, South Africa. Lithos, 91, 352–372.CrossRefGoogle Scholar
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. Mineralogical Magazine, 57, 651–664 CrossRefGoogle Scholar
Nadezhina, T. N., Pushcharovsky, D.Yu. and Khomyakov, A. P. (1987) Refinement of crystal structure of belovite. Mineralogical Zhurnal, 9(2), 45–48 (in Russian).Google Scholar
Oberti, R., Ottolini, L., Delia Ventura, G. and Parodi, G. C. (2001) On the symmetry and crystal chemistry of britholite: New structural and microanalytical data. American Mineralogist, 86, 1066–1075.CrossRefGoogle Scholar
Olivo, G. R. and Williams-Jones, A. E. (1999) Hydrothermal REE-rich eudialyte from the Pilansberg complex, South Africa. The Canadian Mineralogist, 38, 653–663.Google Scholar
Pan, Yu. and Fleet, M. (2002) Compositions of apatite-group minerals: substitution mechanisms and controlling factors. Pp. 13–49 in: Phosphates – Geochemical, Geological, and Materials Importance (Kohn, M. J., Rakovan, J. and Hughes, J. M., editors). Reviews in Mineralogy and Geochemistry, 48. Mineralogical Society of American and the Geochemical Society, Washington, D.C. CrossRefGoogle Scholar
Pekov, I. V. (2001) Lovozero Massif: History of Investigations, Pegmatites, Minerals. Zemlya Press, Moscow, 432 pp. (in Russian).Google Scholar
Pekov, I. V., Chukanov, N. V., Eletskaya, O. V., Khomyakov, A. P. and Menshikov, Yu.P. (1995) Belovite-(Ce): new data, refined formula, and relationships with other minerals of apatite group. Zapiski Vserossiiskogo Mineralogicheskogo Obshchestva, 124(2), 98–110 (in Russian).Google Scholar
Pekov, I. V., Kulikova, I. M., Kabalov, Yu.K., Eletskaya, O. V., Chukanov, N. V., Menshikov, Yu.P. and Khomyakov, A. P. (1996) Belovite-(La), Sr3Na(La,Ce)[PO4]3(F,OH) – a new rare earth mineral of the apatite group. Zapiski Vserossiiskogo Mineralogicheskogo Obshchestva, 125(3), 101–109 (in Russian).Google Scholar
Pushcharovsky, D.Yu., Nadezhina, T. N. and Khomyakov, A. P. (1987) Crystal structure of strontium-apatite from Khibina. Crystallography Reports, 32, 891–895 (in Russian).Google Scholar
Rakovan, J. F. and Hughes, J. M. (2000) Strontium in the apatite structure: strontian fluorapatite and belovite-(Ce). The Canadian Mineralogist, 38, 839–845.CrossRefGoogle Scholar
Ramsay, W. (1890) Geologische Beobachtuntgen auf der Halbinsel Kola. Nebst einem Anhange: Petrographische Beschreibung der Gesteine des Lujavr-urt. Fennia, III, 7, 1–52(in German).Google Scholar
Rastsvetaeva, R. K. and Khomyakov, A. P. (1996) Crystal structure of deloneite-(Ce), a highly ordered Ca-analogue of belovite. Doklady Rossiyskoi Akademii Nauk, 349, 354–357 (in Russian).Google Scholar
Retief, E. A. (1962) Preliminary observations on the feldspars from the Pilanesberg alkaline complex, Transvaal, S. Africa. Norsk Geologisk Tidsskrifi, 42(2), 493–513.Google Scholar
Retief, E. A. (1963) Petrological and mineralogical studies in the southern part of the Pilansberg Complex, Transvaal, South Africa. PhD thesis, Oxford University, Oxford, UK.Google Scholar
Ronsbo, J. G. (1989) Coupled substitutions involving REEs and Na and Si in apatites in alkaline rocks from Ilimaussaq intrusion, South Greenland, and the petrological implications. American Mineralogist, 74, 896–901.Google Scholar
Shand, S. I. (1928) The geology of Pilansberg in the Western Transvaal. Transactions of Geological Society of South Africa, 31, 91–156.Google Scholar
Sood, M. K. and Edgar, A. D. (1970) Melting relations of undersaturated alkaline rocks. Meddelelser om Grønland, 181 pp.Google Scholar
Stormer, J. C., Pierson, M. X. and Tacker, R. C. (1993) Variation of F and Cl X-ray intensity due to anisotropic diffusion in apatite during electron microprobe analysis. American Mineralogist, 78, 641–648.Google Scholar
Zaitsev, A. N. and Chakhmouradian, A. R. (2002) Calcite-amphibole-clinopyroxene rock from the Afrikanda complex, Kola peninsula, Russia: mineralogy and possible link to carbonatites. II. Oxysalt minerals. The Canadian Mineralogist, 40, 103–120.CrossRefGoogle Scholar