Hostname: page-component-848d4c4894-nmvwc Total loading time: 0 Render date: 2024-06-16T06:00:29.518Z Has data issue: false hasContentIssue false

Compositional variation and genesis of pyrochlore, belkovite and baotite from the Sevattur carbonatite complex, India

Published online by Cambridge University Press:  14 April 2021

Monojit Dey
Department of Earth and Climate Science, Indian Institute of Science Education and Research Tirupati, Rami Reddy Nagar, Karakambadi Road, Mangalam, Andhra Pradesh 517507, India
Sourav Bhattacharjee
Department of Earth and Climate Science, Indian Institute of Science Education and Research Tirupati, Rami Reddy Nagar, Karakambadi Road, Mangalam, Andhra Pradesh 517507, India
Aniket Chakrabarty*
Department of Earth and Climate Science, Indian Institute of Science Education and Research Tirupati, Rami Reddy Nagar, Karakambadi Road, Mangalam, Andhra Pradesh 517507, India
Roger H. Mitchell
Department of Geology, Lakehead University, Thunder Bay, Ontario, Canada P7B 5E1
Supriyo Pal
Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
Supratim Pal
Department of Geology, Durgapur Government College, Durgapur, West Bengal 713214, India
Amit Kumar Sen
Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
*Author for correspondence: Aniket Chakrabarty, Email:;


Pyrochlore-group minerals are common in the Neoproterozoic Sevattur carbonatite complex. This complex is composed of dolomite-, calcite-, banded- and blue carbonatite together with pyroxenite, albitite and diverse syenites. This work reports the paragenetic-textural types and compositional variation of pyrochlore hosted by dolomite carbonatite, banded carbonatite and albitite together with that of alteration assemblages containing belkovite and baotite. On the basis of composition, five different types of pyrochlore are recognised and termed Pcl-I through to Pcl-V. The Pb-rich Pcl-I are present exclusively as inclusions in U-rich Pcl-IIa in dolomite carbonatite. The alteration assemblages of Pb-poor Pcl-IIb + Ba-rich or Ba–Si- rich Pcl-IV + belkovite (dolomite carbonatite) and Si-rich Pcl-V + baotite (banded carbonatite) formed after Pcl-IIa differ in these carbonatites. The albitite hosts extremely U-Ti-rich Pcl-III, mantled by Ba-rich potassium feldspar. In common with the banded carbonatite, Pcl-V is formed by alteration of Pcl-III where this mantle is partially, or completely broken. The Ba-Si-enrichment of Pcl-IV and Pcl-V together with the ubiquitous presence of baryte in all Sevattur lithologies suggests late-stage interaction with a Ba-Si-rich acidic hydrothermal fluid. This fluid was responsible for leaching silica from the associated silicates and produced Pcl-V in the silicate-rich lithologies of the banded carbonatite and albitite. The absence of Pcl-V in dolomite carbonatite is a consequence of the low modal abundance of silicates. The complex compositional diversity and lithology specific pyrochlore alteration assemblages suggest that all pyrochlore (Pcl-I to Pcl-IV) were formed initially in an unknown source and transported subsequently in their respective hosts as altered antecrysts.

Article – Gregory Yu. Ivanyuk memorial issue
Copyright © The Author(s), 2021. Published by Cambridge University Press on behalf of The Mineralogical Society of Great Britain and Ireland

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.)


This paper is part of a thematic set ‘Alkaline Rocks’ in memory of Dr. Gregory Yu. Ivanyuk

Associate Editor: Ferdinando Bosi


Ackerman, L., Magna, T., Rapprich, V., Upadhyay, D., Krátký, O., Čejková, B., Erban, V., Kochergina, Y.V. and Hrstka, T. (2017) Contrasting petrogenesis of spatially related carbonatites from Samalpatti and Sevattur, Tamil Nadu, India. Lithos, 284, 257275.CrossRefGoogle Scholar
Akinfiev, N.N., Korzhinskaya, V.S., Kotova, N.P., Redkin, A.F. and Zotov, A.V. (2020) Niobium and tantalum in hydrothermal fluids: Thermodynamic description of hydroxide and hydroxofluoride complexes. Geochimica et Cosmochimica Acta, 280, 102115.CrossRefGoogle Scholar
Andersen, T. (1986) Magmatic fluids in the Fen carbonatite complex, SE Norway. Contributions to Mineralogy and Petrology, 93, 491503.CrossRefGoogle Scholar
Atencio, D., Andrade, M.B., Christy, A.G., Gieré, R. and Kartashov, P.M. (2010) The pyrochlore supergroup of minerals: nomenclature. The Canadian Mineralogist, 48, 673698.CrossRefGoogle Scholar
Bayliss, P., Kaesz, H.D. and Nickel, E.H. (2005) The use of chemical-element adjectival modifiers in mineral nomenclature. The Canadian Mineralogist, 43, 14291433.CrossRefGoogle Scholar
Bonazzi, P., Bindi, L., Zoppi, M., Capitani, G.C. and Olmi, F. (2006) Single-crystal diffraction and transmission electron microscopy studies of “silicified” pyrochlore from Narssârssuk, Julianehaab district, Greenland. American Mineralogist, 91, 794801.CrossRefGoogle Scholar
Bosi, F., Biagioni, C. and Oberti, R. (2019a) On the chemical identification and classification of minerals. Minerals, 9, 591.CrossRefGoogle Scholar
Bosi, F., Hatert, F., Hålenius, U., Pasero, M., Miyawaki, R., and Mills, S.J. (2019b) On the application of the IMA-CNMNC dominant-valency rule to complex mineral compositions. Mineralogical Magazine, 83, 627632.CrossRefGoogle Scholar
Boyle, R.W. (1982) Geochemical prospecting for Thorium and Uranium deposits. Pp. 498 in: Developments in Economic Geology, Elsevier, Amsterdam.Google Scholar
Chakhmouradian, A.R. and Mitchell, R.H. (2002) New data on pyrochlore-and perovskite-group minerals from the Lovozero alkaline complex, Russia. European Journal of Mineralogy, 14, 821836.CrossRefGoogle Scholar
Chakhmouradian, A.R., Reguir, E.P., Kressall, R.D., Crozier, J., Pisiak, L.K., Sidhu, R. and Yang, P. (2015) Carbonatite-hosted niobium deposit at Aley, northern British Columbia (Canada): Mineralogy, geochemistry and petrogenesis. Ore Geology Reviews, 64, 642666.CrossRefGoogle Scholar
Choisnet, J., Nguyen, N., Groult, D. and Raveau, B. (1976) De nouveaux oxydes a reseau forme d'octaedres NbO6 (TaO6) et de groupes Si2O7: Les phases A3Ta6Si4O26 (A = Ba, Sr) et K6M6Si4O26 (M = Nb, Ta). Materials Research Bulletin, 11, 887894.CrossRefGoogle Scholar
Christy, A.G. and Atencio, D. (2013) Clarification of status of species in the pyrochlore supergroup. Mineralogical Magazine, 77, 1320.CrossRefGoogle Scholar
Cooper, A.F. (1996) Nb-rich baotite in carbonatites and fenites at Haast River, New Zealand. Mineralogical magazine, 60, 473482.CrossRefGoogle Scholar
Dey, M., Mitchell, R.H., Bhattacharjee, S., Chakarabarty, A., Pal, S., Pal, S. and Sen, A.K. (2021) Composition and genesis of albitite-hosted antecrystic pyrochlore from the Sevattur carbonatite complex, India. Mineralogical Magazine, 85, Scholar
Doroshkevich, A.G., Viladkar, S.G., Ripp, G.S. and Burtseva, M.V. (2009) Hydrothermal REE mineralization in the Amba Dongar carbonatite complex, Gujarat, India. The Canadian Mineralogist, 47, 11051116.CrossRefGoogle Scholar
Doroshkevich, A.G., Veksler, I.V., Klemd, R., Khromova, A.E. and Izbrodin, I.A. (2017) Trace element composition of minerals and rocks in the Belaya Zima carbonatite complex (Russia):implications for the mechanisms of magma evolution and carbonatite formation. Lithos, 284–285, 91108.CrossRefGoogle Scholar
Dumańska-Słowik, M., Pieczka, A., Tempesta, G., Olejniczak, Z. and Heflik, W. (2014) “Silicified” pyrochlore from nepheline syenite (mariupolite) of the Mariupol Massif, SE Ukraine: A new insight into the role of silicon in the pyrochlore structure. American Mineralogist, 99, 20082017.CrossRefGoogle Scholar
Elliott, H.A.L., Wall, F., Chakhmouradian, A.R., Siegfried, P.R., Dahlgren, S., Weatherley, S., Finch, A.A., Marks, M.A.W., Dowman, E. and Deady, E. (2018) Fenites associated with carbonatite complexes: A review. Ore Geology Reviews, 93, 3859.CrossRefGoogle Scholar
Friis, H. and Casey, W.H. (2018) Niobium is highly mobile as a polyoxometalate ion during natural weathering. The Canadian Mineralogist, 56, 905912.CrossRefGoogle Scholar
Geisler, T., Berndt, J., Meyer, H.W., Pollok, K. and Putnis, A. (2004) Low-temperature aqueous alteration of crystalline pyrochlore: correspondence between nature and experiment. Mineralogical Magazine, 68, 905922.CrossRefGoogle Scholar
Giovannini, A.L., Mitchell, R.H., Neto, A.C.B., Moura, C.A., Pereira, V.P. and Porto, C.G. (2020) Mineralogy and geochemistry of the Morro dos Seis Lagos siderite carbonatite, Amazonas, Brazil. Lithos, 360, 105433.CrossRefGoogle Scholar
Harris, P.M. (1965) Pandaite from the Mrima Hill niobium deposit (Kenya). Mineralogical Magazine, 35, 277290.CrossRefGoogle Scholar
Hatert, F. and Burke, E.A. (2008) The IMA–CNMNC dominant-constituent rule revisited and extended. The Canadian Mineralogist, 46, 717728.CrossRefGoogle Scholar
Hogarth, D.D. (1977) Classification and nomenclature of the pyrochlore group. American Mineralogist, 62, 403410.Google Scholar
Hogarth, D.D., Williams, C.T. and Jones, P. (2000) Primary zoning in pyrochlore group minerals from carbonatites. Mineralogical Magazine, 64, 683697.CrossRefGoogle Scholar
Jäger, E., Niggli, E. and Van der Veen, A.H. (1959) A hydrated barium-strontium pyrochlore in a biotite rock from Panda Hill, Tanganyika 1. Mineralogical Magazine, 32, 1025.CrossRefGoogle Scholar
Karup-Møller, S. (2018) Uranium-rich pyrochlores from the Iimaussaq complex, South Greenland. Neues Jahrbuch für Mineralogie–Abhandlungen/Journal of Mineralogy and Geochemistry, 195, 177190.CrossRefGoogle Scholar
Kaur, G., and Mitchell, R.H. (2019) Mineralogy of the baotite-bearing Gundrapalli lamproite, Nalgonda district, Telangana, India. Mineralogical Magazine, 83, 401411.CrossRefGoogle Scholar
Khromova, E.A., Doroshkevich, A.G., Sharygin, V.V. and Izbrodin, L.A. (2017) Compositional evolution of pyrochlore-group minerals in carbonatites of the Belaya Zima Pluton, Eastern Sayan. Geology of Ore Deposits, 59, 752764.CrossRefGoogle Scholar
Krishnamurthy, P. (1977) On some geochemical aspects of the Sevattur carbonatite complex, North Arcot District, Tamil Nadu. Journal of the Geological Society of India, 18, 265274Google Scholar
Krishnamurthy, P. (2019) Carbonatites of India. Journal of the Geological Society of India, 94, 117138.CrossRefGoogle Scholar
Krmíček, L., Cempírek, J., Havlín, A., Přichystal, A., Houzar, S., Krmíčková, M. and Gadas, P. (2011) Mineralogy and petrogenesis of a Ba–Ti–Zr-rich peralkaline dyke from Šebkovice (Czech Republic): recognition of the most lamproitic Variscan intrusion. Lithos, 121, 7486.CrossRefGoogle Scholar
Kullerud, K., Zozulya, D., and Ravna, E.J. (2012) Formation of baotite-a Cl-rich silicate-together with fluorapatite and F-rich hydrous silicates in the Kvaløya lamproite dyke, North Norway. Mineralogy and Petrology, 105,145156.CrossRefGoogle Scholar
Lumpkin, G.R. and Ewing, R.C. (1995) Geochemical alteration of pyrochlore group minerals: pyrochlore subgroup. American Mineralogist, 80, 732743.CrossRefGoogle Scholar
Lumpkin, G.R. and Ewing, R.C. (1996) Geochemical alteration of pyrochlore group minerals: Betafite subgroup. American Mineralogist, 81, 12371248.CrossRefGoogle Scholar
Lumpkin, G.R., and Mariano, A.N. (1995) Natural occurrence and stability of pyrochlore in carbonatites, related hydrothermal systems, and weathering environments. MRS Online Proceedings Library Archive, 412, 831838.CrossRefGoogle Scholar
Mariano, A.N. (1989) Nature of economic mineralization in carbonatites and related rocks. Pp. 149176 in: Carbonatites: Genesis and Evolution. Unwin Hyman, London.Google Scholar
Melgarejo, J.C., Costanzo, A., Bambi, A.C., Gonçalves, A.O. and Neto, A.B. (2012) Subsolidus processes as a key factor on the distribution of Nb species in plutonic carbonatites: The Tchivira case, Angola. Lithos, 152, 187201.CrossRefGoogle Scholar
Migdisov, A.A., Boukhalfa, H., Timofeev, A., Runde, W., Roback, R. and Williams-Jones, A.E. (2018) A spectroscopic study of uranyl speciation in chloride-bearing solutions at temperatures up to 250° C. Geochimica et Cosmochimica Acta, 222, 130145.CrossRefGoogle Scholar
Mitchell, R.H. (2015) Primary and secondary niobium mineral deposits associated with carbonatites. Ore Geology Reviews, 64, 626641.CrossRefGoogle Scholar
Mitchell, R.H. and Smith, D.L. (2017) Geology and mineralogy of the Ashram Zone carbonatite, Eldor Complex, Québec. Ore Geology Reviews, 86, 784806.CrossRefGoogle Scholar
Mitchell, R.H., Wahl, R. and Cohen, A. (2020) Mineralogy and genesis of pyrochlore apatitite from The Good Hope Carbonatite, Ontario: A potential niobium deposit. Mineralogical Magazine, 84, 8191.CrossRefGoogle Scholar
Nasraoui, M. and Bilal, E. (2000) Pyrochlores from the Lueshe carbonatite complex (Democratic Republic of Congo): a geochemical record of different alteration stages. Journal of Asian Earth Sciences, 18, 237251.CrossRefGoogle Scholar
Nekrasov, J.V., Ponomarev, V.I., Simonov, V.I. and Kheiker, D.M. (1969) A more precise determination of the atomic structure of baotite, and isomorphic relations in this mineral. Kristallographyia, 14, 602609.Google Scholar
Nemec, D. (1987) Baotite – a rock-forming mineral of Ba-rich hyperpotassic dyke rocks. Neues Jahrb Mineral Monatshefte, 1, 3142.Google Scholar
Peng, C.J. (1959) The discovery of several new minerals of rare elements. American Mineralogist, 45, 745.Google Scholar
Potter, E.G. and Mitchell, R.H. (2005) Mineralogy of the Deadhorse Creek volcaniclastic breccia complex, northwestern Ontario, Canada. Contributions to Mineralogy and Petrology, 150, 212229.CrossRefGoogle Scholar
Pressacco, R. (2001) Geology of the Cargill Township Residual Carbonatite-associated Phosphate Deposit, Kapuskasing, Ontario. Exploration and Mining Geology, 10, 7784.CrossRefGoogle Scholar
Ramasamy, R., Gwalani, L.G. and Subramanian, S.P. (2001) A note on the occurrence and formation of magnetite in the carbonatites of Sevvattur, North Arcot district, Tamil Nadu, Southern India. Journal of Asian Earth Sciences, 19, 297304.CrossRefGoogle Scholar
Rukhlov, A.S. and Bell, K. (2010) Geochronology of carbonatites from the Canadian and Baltic Shields, and the Canadian Cordillera: clues to mantle evolution. Mineralogy and Petrology, 98, 1154.CrossRefGoogle Scholar
Schleicher, H. (2019) In-situ determination of trace element and REE partitioning in a natural apatite-carbonatite melt system using synchrotron XRF microprobe analysis. Journal of the Geological Society of India, 93, 305312.CrossRefGoogle Scholar
Schleicher, H., Kramm, U., Pernicka, E., Schidlowski, M., Schmidt, F., Subramanian, V., Todt, W. and Viladkar, S.G. (1998) Enriched subcontinental upper mantle beneath southern India: evidence from Pb, Nd, Sr, and C–O isotopic studies on Tamil Nadu carbonatites. Journal of Petrology, 39, 17651785.CrossRefGoogle Scholar
Semenov, E.I., Khun, V.S. and Kapitonova, T.A. (1961) Baotite, a new niobian mineral. Doklady AN USSR, 136, 915916 [in Russian].Google Scholar
Sharygin, V.V., Sobolev, N.V. and Channer, D.M.D. (2009) Oscillatory-zoned crystals of pyrochlore-group minerals from the Guaniamo kimberlites, Venezuela. Lithos, 112, 976985.CrossRefGoogle Scholar
Sorokhtina, N.V., Voloshin, A.V. and Pakhomovsky, Ya.A. (1998) Belkovite from calcite-dolomite carbonatites of the Sebljavr massif (Kola Peninsula). Zapiski Vserossiiskogo Mineralogicheskogo Obshchestva, 127, 7984 [in Russian].Google Scholar
Sorokhtina, N.V., Kogarko, L.N. and Shpachenko, A.K. (2010) New data on mineralogy and geochemistry of rare-metal mineralization of the Gremiakha-Vyrmes Massif. Doklady Earth Sciences, 434, 243247.CrossRefGoogle Scholar
Subramaniam, V., Viladkar, S.G. and Upendran, R. (1978) Carbonatite alkali complex of Samalpatti, Dharmapuri district, Tamil Nadu. Journal of the Geological Society of India, 19, 206216.Google Scholar
Timofeev, A. and Williams-Jones, A.E. (2015) The origin of niobium and tantalum mineralization in the Nechalacho REE Deposit, NWT, Canada. Economic Geology, 110, 17191735.CrossRefGoogle Scholar
Timofeev, A., Migdisov, A.A., and Williams-Jones, A.E. (2017) An experimental study of the solubility and speciation of tantalum in fluoride-bearing aqueous solutions at elevated temperature. Geochimica et Cosmochimica Acta, 197, 294304.CrossRefGoogle Scholar
Timofeev, A., Migdisov, A.A., Williams-Jones, A.E., Roback, R., Nelson, A.T. and Xu, H. (2018) Uranium transport in acidic brines under reducing conditions. Nature communications, 9, 17.CrossRefGoogle ScholarPubMed
Traversa, G., Gomes, C.B., Brotzu, P., Buraglini, N., Morbidelli, L., Principato, M.S., Ronca, S. and Ruberti, E. (2001) Petrography and mineral chemistry of carbonatites and mica-rich rocks from the Araxá complex (Alto Paranaíba Province, Brazil). Anais da Academia Brasileira de Ciências, 73, 7198.CrossRefGoogle Scholar
Udas, G.R. and Krishnamurthy, P. (1970) Carbonatites of Sevathur and Jokipatti, Madras State, India, Proceedings of Indian National Science Academy, 36, 331343.Google Scholar
Uher, P., Černy, P., Chapman, R., Hatar, J. and Miko, O. (1998) Evolution of Nb,Ta-oxide minerals in the Prašivá granitic pegmatites, Slovakia. II. External hydrothermal Pb,Sb overprint. The Canadian Mineralogist; 36, 535545.Google Scholar
Viladkar, S.G. and Bismayer, U. (2010) Compositional variation in pyrochlores of Amba Dongar carbonatite complex, Gujarat. Journal of the Geological Society of India, 75, 495502.CrossRefGoogle Scholar
Viladkar, S.G. and Bismayer, U. (2014) U-rich pyrochlore from Sevathur carbonatites, Tamil Nadu. Journal of the Geological Society of India, 83, 175182.CrossRefGoogle Scholar
Viladkar, S.G. and Subramanian, V. (1995) Mineralogy and geochemistry of the carbonatites of the Sevathur and Samalpatti complexes, Tamil-Nadu. Journal of the Geological Society of India, 45, 505517.Google Scholar
Voloshin, A.V., Pakhomovsky, Y.A., Pushcharovsky, D.Y., Nadezhina, T.N., Bakhchisaraitsev, A.Y. and Kobyashev, Y.S. (1989) Strontiopyrochlore: composition and structure. Trudy Mineralogicheskogo Muzeya AN SSSR, 36, 1224 [in Russian].Google Scholar
Voloshin, A.V., Subbotin, V.V., Pakhomovsky, Y.A., Bakhchisaraytsev, A.Y., Yamnova, N.A. and Pushcharovsky, D.Y. (1990) Belkovite Ba2(Nb,Ti)6(Si2O7)2O12. A new mineral from carbonatite of the Vuoriyarvi pluton (Kola Peninsula). Transactions (Doklady) of the USSR Academy of Sciences. Earth Science Sections, 315, 229232.Google Scholar
Voloshin, A.V., Subbotin, V.V., Pakhomovsky, Y.A., Bakhchisaraitsev, A.Y. and Yamnova, N.A. (1991) Belkovite – a new barium-niobium silicate from carbonatites of the Vuoriyarvi massif (Kola Peninsula, USSR). Neues Jahrbuch für Mineralogie Monatshefte, 1, 2331.Google Scholar
Wall, F., Williams, C.T., Woolley, A.R. and Nasraoui, M. (1996) Pyrochlore from weathered carbonatite at Lueshe, Zaire. Mineralogical Magazine, 60, 731750.CrossRefGoogle Scholar
Walter, B.F., Parsapoor, A., Braunger, S., Marks, M.A.W., Wenzel, T., Martin, M. and Markl, G. (2018) Pyrochlore as a monitor for magmatic and hydrothermal processes in carbonatites from the Kaiserstuhl volcanic complex (SW Germany). Chemical Geology, 498, 116.CrossRefGoogle Scholar
Williams, C.T., Wall, F., Woolley, A.R. and Phillipo, S. (1997) Compositional variation in pyrochlore from the Bingo carbonatite, Zaire. Journal of African Earth Sciences, 25, 137145.CrossRefGoogle Scholar
Zurevinski, S.E. and Mitchell, R.H. (2004) Extreme compositional variation of pyrochlore-group minerals at the Oka carbonatite complex, Quebec: evidence of magma mixing? The Canadian Mineralogist, 42, 11591168.CrossRefGoogle Scholar
Supplementary material: File

Dey et al. supplementary material

Dey et al. supplementary material

Download Dey et al. supplementary material(File)
File 79.2 KB