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Kuratite, Ca4(Fe2+10Ti2)O4[Si8Al4O36], the Fe2+-analogue of rhönite, a new mineral from the D'Orbigny angrite meteorite

Published online by Cambridge University Press:  02 January 2018

S.-L. Hwang*
Affiliation:
Department of Materials Science and Engineering, National Dong Hwa University, Hualien, Taiwan, ROC
P. Shen
Affiliation:
Department of Materials Science and Optoelectronic Science, National Sun Yat-sen University, Kaohsiung, Taiwan, ROC
H.-T. Chu
Affiliation:
Central Geological Survey, PO Box 968, Taipei, Taiwan, ROC
T.-F. Yui
Affiliation:
Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC
M.-E. Varela
Affiliation:
Instituto de Ciencias Astronómicas de la Tierra y del Espacio (ICATE)Avenida España 1512 sur, J5402DSP, San Juan,Argentina
Y. Iizuka
Affiliation:
Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC
*

Abstract

Kuratite, ideally Ca4(Fe2+10Ti2)O4[Si8Al4O36], the Fe2+-analogue of rhönite and a new member of the sapphirine supergroup, was identified from the D'Orbigny angrite meteorite by electron microscopy and micro-Raman spectroscopy. Based on the least-squares refinement of 25 d-spacings measured from selected-area electron diffraction patterns of 11 zone axes, the symmetry of kuratite was shown to be triclinic (space group by analogy to rhönite) with a = 10.513(7), b = 10.887(7), c = 9.004(18) Å, α = 105.97(13), β = 96.00(12), γ = 124.82(04)°, V = 767 ± 2 Å3 and Z = 1 for the 40 oxygen formula. The empirical formula based on eight electron microprobe analyses is (Ca3.88Na0.02REE3+0.03Mn0.03Mg0.01Ni0.02Zn0.01Sr0.01)∑4.01 (Fe2+9.989.9Ti2.00)∑11.98(Si7.80Al3.52Fe3+0.64P0.05S0.02)∑12.03O39.98F0.01Cl0.01. The simplified formula is Ca4(Fe2+10Ti2)O4[Si8Al4O36]. Micro-Raman spectroscopy showed four main bands resembling those of lunar rhönite but with higher frequencies due to different chemical composition. Analogous to the occurrence of kuratite in terrestrial basaltic rocks, kuratite coexisting with Al, Ti-bearing hedenbergite, ulvöspinel, iron-sulfide, tsangpoite, Ca-rich fayalite and kirschsteinite in D'Orbigny angrite most probably was formed at >1000°C by rapid cooling of an interstitial melt, which is subsilicic, almost Mg-free but enriched in Al-P-Ca-Ti-Fe.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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References

Bonaccorsi, E., Merlino, S. and Pasero, M. (1990) Rhönite: structural and microstructural features, crystal chemistry and polysomatic relationships. European Journal of Mineralogy, 2, 203218.CrossRefGoogle Scholar
Gamble, J.A. and Kyle, P.R. (1987) The origins of glass and amphibole in spinel-wehrlite xenoliths from Foster Crater, McMurdo Volcanic Group, Antarctica. Journal of Petrology, 28, 755779.CrossRefGoogle Scholar
Grapes, R. and Keller, J. (2010) Fe +-dominant rhönite in undersaturated alkaline basaltic rocks, Kaiserstuhl volcanic complex, Upper Rhine Graben, SW Germany. European Journal of Mineralogy, 22, 285292.CrossRefGoogle Scholar
Grew, E.S., Barbier, J., Britten, J., Yates, M.G., Polyakov, V.O., Shcherbakova, E.P., Halenius, U. and Shearer, C.K. (2005) Makarochkinite, Ca2Fe42+Fe3+TiSi4BeAlO20, a new bery llo silicate member of the aenigmatite- sapphirine-surinamite group from the Il’men Mountains (southern Urals), Russia. American Mineralogist, 90, 14021412.CrossRefGoogle Scholar
Grew, E.S., Hålenius, U., Pasero, M. and Barbier, J. (2008) Recommended nomenclature for the sapphir-ine and surinamite groups (sapphirine supergroup). Mineralogical Magazine, 90, 839—876.CrossRefGoogle Scholar
Grünhagen, H. and Seck, H.A. (1972) Rhönite aus einem Melaphonolith vom Puy de Saint-Sandoux (Auvergne). Tschermaks Mineralogische und Petrographische Mitteilungen, 18, 17—38.CrossRefGoogle Scholar
Havette, A., Clocchiatti, R., Nativel, P. and Montaggioni, L.F. (1982) Une paragenese inhabituelle à fassaïte, mélilite et rhönite dans un basalte alcalin contaminé au contact d'un récif coralline (Saint-Leu, Ile de la Réunion). Bulletin de Minéralogie, 105, 364375.CrossRefGoogle Scholar
Hwang, S.-L., Shen, P., Chu, H.-T., Yui, T.-F., Varela, M.E. and Iizuka, Y (2015) Tsangpoite, IMA 2014-110. CNMNC Newsletter No. 25, June 2015, page 533. Mineralogical Magazine, 79, 529—535.Google Scholar
Jambon, A. and Boudouma, O. (2011) Evidence for rhönite in angrites D'Orbigny and Sahara 99555 (abstract). Meteoritics and Planetary Science, 46 Supplement, A113.Google Scholar
Keil, K. (2012) Angrites, a small but diverse suite of ancient, silica-undersaturated volcanic-plutonic mafic meteorites, and the history of their parent asteroid. Chemie der Erde, 72, 191218.CrossRefGoogle Scholar
Kuehner, S.M. and Irving, A.J. (2007) Primary ferric iron-bearing rhönite in plutonic igneous 232 angrite NWA 4590: implications for redox conditions on the angrite parent body. Eos, AGU, 88, Fall Meeting Supplement, Abstract P41A-0219.Google Scholar
Kunzmann, T. (1999) The aenigmatite-rhönite mineral group. European Journal of Mineralogy, 11, 743—756.CrossRefGoogle Scholar
Kurat, G., Varela, M.E., Brandstätter, F., Weckwerth, G., Clayton, R., Weber, H.W., Schultz, L., Wäsch, E. and Nazarov, M.A. (2004) D'Orbigny: A non-igneous angritic achondrite. Geochimica et Cosmochimica Acta, 68, 19011921.CrossRefGoogle Scholar
Mittlefehldt, D.W., Killgore, M. and Lee, M.T. (2002) Petrology and geochemistry of D'Orbigny, geochemistry of Sahara 99555, and the origins of angrites. Meteoritics and Planetary Science, 37, 345369.CrossRefGoogle Scholar
Mukhopadhyay, D.K. and Lindsley, D.H. (1983) Phase relations in the join kirschsteinite (CaFeSiO4)-fayalite (Fe2SiO4). American Mineralogist, 68, 10891094.Google Scholar
Nickel, E.H. and Grice, J.D. (1998) The IMA Commission on New Minerals and Mineral Names: procedures and guidelines on mineral nomenclature. The Canadian Mineralogist, 36, 913926.Google Scholar
Olsson, H.B. (1983) Rhönite from Skåne (Scania), southern Sweden. Geologiska Föreningen i Stockholm Förhandlingar, 105, 281286.CrossRefGoogle Scholar
Smith, D.G.W.. and Nickel, E.H. (2007) A system for codification for unnamed minerals: report of the Subcommittee for Unnamed Minerals of the IMA Commission on New Minerals, Nomenclature and Classification. The Canadian Mineralogist, 45, 9831055.CrossRefGoogle Scholar
Treiman, A.H. (2008) Rhönite in Luna 24 pyroxenes: first find from the Moon, and implications for volatiles in planetary magmas. American Mineralogist, 93, 488–91.CrossRefGoogle Scholar
Varela, M.E., Kurat, G., Zinner, E., Métrich, N., Brandstätter, F., Natflos, T and Sylvester, P. (2003) Glasses in the D'Orbigny angrite. Geochimica et Cosmochimica Acta, 67, 50275046.CrossRefGoogle Scholar
Varela, M.E., Kurat, G., Zinner, E., Hoppe, P., Ntaflos, T. and Nazarov, M.A. (2005) The non-igneous genesis of angrites: support from trace element distribution between phases in D'Orbigny. Meteoritics and Planetary Science, 40, 409–130.CrossRefGoogle Scholar