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Contrasts in gem corundum characteristics, eastern Australian basaltic fields: trace elements, fluid/melt inclusions and oxygen isotopes

Published online by Cambridge University Press:  05 July 2018

Khin Zaw*
Affiliation:
CODES ARC Centre of Excellence in Ore Deposits, University of Tasmania, Private Bag 79, Hobart, Tasmania 7001, Australia
F. L. Sutherland
Affiliation:
Mineralogy, Australian Museum, 6 College Street, Sydney, NSW 2010, Australia
F. Dellapasqua
Affiliation:
CODES ARC Centre of Excellence in Ore Deposits, University of Tasmania, Private Bag 79, Hobart, Tasmania 7001, Australia
C. G. Ryan
Affiliation:
CSIRO Exploration and Mining, School of Physics, University of Melbourne, VIC 3010, Australia
Tzen-Fu Yui
Affiliation:
Institute of Earth Science, Academica Sinica, Taipei, Taiwan
T. P. Mernagh
Affiliation:
Australian Geological Survey Organization, Canberra, ACT 2601, Australia
D. Duncan
Affiliation:
McPherson Duncan & Associates, 18 Old Summerleas Road, Kinston, Tasmania 7050, Australia

Abstract

Corundum xenocrysts from alkaline basalt fields differ in characteristics and hence lithospheric origins. Trace element, fluid/melt inclusion and oxygen isotope studies on two eastern Australian corundum deposits are compared to consider their origins. Sapphires from Weldborough, NE Tasmania, are magmatic (high-Ga, av. 200 ppm) and dominated by Fe (av. 3300 ppm) and variable Ti (av. 400 ppm) as chromophores. They contain Cl, Fe, Ga, Ti and CO2-rich fluid inclusions and give δ18O values (5.1–6.2‰) of mantle range. Geochronology on companion zircons suggests several sources (from 290 Ma to 47 Ma) were disrupted by basaltic melts (47 ± 0.6 Ma). Gem corundums from Barrington, New South Wales, also include magmatic sapphires (Ga av. 170 ppm; δ18O (4.6–5.8‰), but with more Fe (av. 9000 ppm) and less Ti (av. 300 ppm) as chromophores. Zircon dating suggests that gem formation preceded and was overlapped by Cenozoic basaltic melt generation (59–4 Ma). In contrast, a metamorphic sapphire-ruby suite (low-Ga, av. 30 ppm) here incorporates greater Cr into the chromophores (up to 2250 ppm). Fluid inclusions are CO2-poor, but melt inclusions suggest some alkaline melt interaction. The δ18O values (5.1–6.2‰) overlap magmatic sapphire values. Interactions at contact zones (T = 780–940°C) between earlier Permian ultramafic bodies and later alkaline fluid activity may explain the formation of rubies.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2006

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References

Bottrill, R.S. (1996) Corundum and Sapphire in Tasmania. Tasmanian Geological Survey, Record 1996/05 (unpublished).Google Scholar
Bottrill, R.S. (1998) A corundum-quartz assemblage in altered volcanic rocks, Bond Range, Tasmania. Mineralogical Magazine, 62, 325332.CrossRefGoogle Scholar
Campbell, J.L. and Czamanske, G.K. (1998) Micro-PIXE in Earth science. Pp. 169185 in: Particle-Induced X-ray Emission Spectrometry (Johansson, S.A.E., Campbell, J.L. and Malmqvist, K.G., editors). Chemical Analysis Series, 133, Wiley, New York.Google Scholar
Coenraads, R.R., Sutherland, F.L. and Kinny, P.D. (1990) The origin of sapphires: U-Pb dating of zircon inclusions sheds new light. Mineralogical Magazine, 54, 113122.CrossRefGoogle Scholar
Coldham, T. (2003) The history and importance of heat treatment of Australian sapphire. The Australian Gemmologist, 21, 5062.Google Scholar
Crawford, A.J., Lanyon, R., Elmes, M. and Eggins, S. (1997) Geochemistry and significance of basaltic rocks dredged from the South Tasman Rise and adjacent seamounts. Australian Journal of Earth Sciences, 44, 621632.CrossRefGoogle Scholar
Everard, J.L., Sutherland, F.L. and Zwingmann, H. (2004) A Cretaceous phonolite from the Tomahawk River, Northeast Tasmania. Papers and Proceedings of the Royal Society of Tasmania, 138, 1133.CrossRefGoogle Scholar
Garnier, V., Giuliani, G., Ohnenstetter, D. and Schwarz, D. (2004) Les gizements de corindon: classification et genese. Les placers a corindon gemme. Le Regne Mineral, 55, 747.Google Scholar
Garnier, V., Ohnenstetter, D., Giuliani, G., Fallick, A.E., Phan Trong, T., Hoang Quang, L., Pham Van, L. and Schwarz, D. (2005) Basalt petrology, zircon ages and sapphire genesis from Dak Nong, southern Vietnam. Mineralogical Magazine, 69, 2138.CrossRefGoogle Scholar
Giuliani, G., Fallick, A.E., Garnier, V., France-Lanord, C., Ohnenstetter, D. and Schwarz, D. (2005) Oxygen isotope compositions as a tracer for the origins of rubies and sapphires. Geology, 33, 249252.CrossRefGoogle Scholar
Gunn, P.J., Mitchell, J.N. and Meixner, T.J. (1996) The structure and evolution of the Bass and Durroon Basins as delineated by aeromagnetic data. Australian Geological Survey Organisation Record, 1996/14 (unpublished).Google Scholar
Guo, J.F., O'Reilly, S.Y. and Griffin, W.L. (1996) Corundum from basaltic terrains: a mineral inclusion approach to the enigma. Contributions to Mineralogy and Petrology, 111, 368386.CrossRefGoogle Scholar
Irving, A.J. (1986) Polybasic magma mixing in alkali basalts and kimberlites: Evidence for corundum, zircon and ilmenite megacrysts. Geological Society of Australia Abstracts Series, 16, 262264.Google Scholar
Lanyon, R., Varne, R. and Crawford, A.J. (1993) Tasmanian Tertiary basalts, the Balleny Plume, and opening of the Tasman Sea (southwest Pacific Ocean). Geology, 21, 555558.2.3.CO;2>CrossRefGoogle Scholar
Limtrakun, P., Zaw, Khin, Ryan, C.G. and Mernagh, J.P. (2001) Formation of the Denchai gem sapphires, northern Thailand: evidence from mineral chemistry and fluid/melt inclusion characteristics. Mineralogical Magazine, 65, 725735.CrossRefGoogle Scholar
Maxwell, J.A., Teesdale, W.J. and Campbell, J.L. (1995) The Geulph PIXE software package II. Nuclear Instruments and Methods in Physics Research, B95, 407421.CrossRefGoogle Scholar
McClenaghan, M.P., Turner, N.J., Baillie, P.W., Brown, A.V., Williams, P.R. and Moore, W.R. (1982) Geology of the Ringarooma-Boobyalla area. Tasmanian Department of Mines, Bulletin of the Geological Survey of Tasmania, 9, 198 pp.Google Scholar
Monchoux, P. (1972) Roches à sapphirine au contract des lherzolites pyrénéennes. Contributions to Mineralogy and Petrology, 37, 4764.CrossRefGoogle Scholar
Monchoux, P., Fontan, F., Parseval, P. de, Martin, R.F. and Wang, R.C. (2006) Igneous albititic dikes in orogenic lherzolites, Western Pyrenees, France: a possible source for corundum and alkali feldspar xenocrysts in basaltic terranes. I. Mineral Associations. The Canadian Mineralogist, 44, 817842.CrossRefGoogle Scholar
Moore, W.R. (1991) Geology-Winnaleah 1:100, 000. Tasmanian Department of Resources and Energy, Hobart.Google Scholar
Morris, P.A. (1984) MAGFRAC: A basic program for least-squares approximation of fractionational crystallisation. Computers and Geoscience, 19, 437444.CrossRefGoogle Scholar
Oakes, G.M., Barron, L.M. and Lishmund, S.R. (1996) Alkali basalts and associated volcaniclastic rocks as a source of sapphire in eastern Australia. Australian Journal of Earth Science, 43, 289298.CrossRefGoogle Scholar
O'Neil, C., Moresi, L., Lenardic, A. and Cooper, C.M. (2003) Inferences on Australia's heat flow and thermal structure from mantle convection modelling results. Geological Society of Australia Special Publication, 22, and Geological Society of America Special Paper, 372, 169184.Google Scholar
O'Reilly, S.Y. and Zhang, M. (1995) Geochemical characteristics of lava-field basalts from eastern Australia and inferred sources: connections with the sub-continental lithospheric mantle. Contributions to Mineralogy and Petrology, 121, 148170.CrossRefGoogle Scholar
Peucat, J.J., Ruffault, P., Fritsch, E., Simonet, C., Bouhnik-Le, C. and Lasnier, B. (2005) Un nouvel outil géochimique de reconnaissance des saphirs bleus basaltiques et metamorphiques: Le rapport Ga/Mg. Revue de Gemmologie, 152, 15.Google Scholar
Pin, C, Monchoux, P., Paquette, J.-L., Azambre, B., Wang, P.C. and Martin, R.F. (2006) Igneous albititic dikes in orogenic lherzolites, Western Pyrenees, France: a possible source for corundum and alkali feldspar xenocrysts in basalt terranes. II. Geochemical and petrogenetic considerations. The Canadian Mineralogist, 44, 843856.CrossRefGoogle Scholar
Rawlinson, N., Houseman, G.A., Collins, C.D.N. and Drummond, B.J. (2001) New evidence of Tasmania's tectonic history from a novel seismic experiment. Geophysical Research Letters, 28, 33373340.CrossRefGoogle Scholar
Roberts, D.L., Sutherland, F.L., Hollis, J.D., Kennewell, P. and Graham, I.T. (2004) Gemstone characteristics, North-East Barrington Plateau, NSW. Journal & Proceedings of the Royal Society of New South Wales, 137, 99122.Google Scholar
Ryan, C.G., Heinrick, C.A., van Achterbergh, E., Balhaus, C. and Mernagh, T.P. (1995) Microanalysis of ore-forming fluids using the scanning proton microprobe. Nuclear Instrument Method, B104, 182190.CrossRefGoogle Scholar
Ryan, C.G., van Achterbergh, E., Yeates, C., Drieberg, S.L., Mark, G., McInnes, B.M., Win, T.T. and Suter, G.F. (2002) Quantitative, high sensitive, high resolution, nuclear microprobe imaging of fluids, melts and minerals. Nuclear Instrument Method, B188, 1827.CrossRefGoogle Scholar
Saminpanya, S., Manning, D.A.C., Droop, G.T.R. and Henderson, C.M.B. (2003) Trace elements in Thai gem corundums. Journal of Gemmology, 28, 392398.Google Scholar
Sharp, Z.D. (1990) A laser-based microanalytical method for the in situ determination of oxygen isotope ratios of silicates and oxides. Geochimica et Cosmochimica Acta, 54, 13531357.CrossRefGoogle Scholar
Siedner, G. (1965) Geochemical features of a strongly fractionated alkali igneous suite. Geochimica et Cosmochimica Acta, 29, 113137.CrossRefGoogle Scholar
Simonet, C., Paquette, J.L., C., Pin, Lasnier, B. and Fritsch, E. (2004) The Dusi (Garba Tula) sapphire deposit, Central Kenya – a unique Pan-African corundum-bearing monzonite, Journal of African Earth Sciences, 38, 401410.CrossRefGoogle Scholar
Sun, S.-S. and McDonough, W.F. (1989) Chemical and isotopic systematics of oceanic basalts: implications for mantle composition and processes. Pp. 313345 in: Magmatism in the Ocean Basins. Special Publication, 42, Geological Society, London.Google Scholar
Sutherland, F.L. (1996) Alkaline rocks and gemstones, Australia: a review and synthesis. Australian Journal of Earth Sciences, 43, 323343.CrossRefGoogle Scholar
Sutherland, F.L. and Coenraads, R.R. (1996) An unusual ruby-sapphirine-spinel assemblage from the Tertiary Barrington volcanic province, New South Wales. Mineraogical Magagazine, 60, 623638.CrossRefGoogle Scholar
Sutherland, F.L. and Fanning, C.M. (2001) Gem-bearing basaltic volcanism, Barrington New South Wales: Cenozoic evolution based on basalt K-Ar ages and zircon fission track and U-Pb isotope dating. Australian Journal of Earth Sciences, 48, 221237.CrossRefGoogle Scholar
Sutherland, F.L. and Graham, I.T. (2003) Geology of the Barrington Tops Plateau. Its Rocks, Minerals and Gemstones, New South Wales, Australia. The Australian Museum Society, Sydney, 56 pp.Google Scholar
Sutherland, F.L. and Schwarz, D. (2001) Origin of gem corundums from basaltic fields. The Australian Gemmologist, 21, 3033.Google Scholar
Sutherland, F.L. and Wellman, P. (1986) Potassium-argon ages of Tertiary volcanic rocks, Tasmania. Papers and Proceedings of the Royal Society of Tasmania, 120, 7786.CrossRefGoogle Scholar
Sutherland, F.L., Schwarz, D., Jobbins, E.A., Coenraads, R.R. and Webb, G. (1998 a) Distinctive gem corundum suites from discrete basalt fields: a comparative study of Barrington, Australia and West Pailin, Cambodia, gemfields. Journal of Gemmology, 26, 6585.CrossRefGoogle Scholar
Sutherland, F.L., Hoskin, P.W.O., Fanning, C.M. and Coenraads, R.R. (1998 b) Models of corundum origin from alkali basalt terrains: A reappraisal. Contributions to Mineralogy and Petrology, 133, 356-72.CrossRefGoogle Scholar
Sutherland, F.L., Graham, I.T., Pogson, R.E., Schwarz, D., Webb, G.B., Coenraads, R.R., Fanning, C.M., Hollis, J.D. and Allen, T.C. (2002 a) The Tumbarumba basaltic gem field, New South Wales: In relation to sapphire-ruby deposits of eastern Australia. Records of the Australian Museum, 54, 215248.CrossRefGoogle Scholar
Sutherland, F.L., Bosshart, G., Fanning, C.M., Hoskin, P.W.O. and Coenraads, R.R. (2002 b) Sapphire crystallisation age and origin, Ban Huai Sai, Laos: age based on zircon inclusions. Journal of Asian Earth Sciences, 20, 841849.CrossRefGoogle Scholar
Sutherland, F.L., Coenraads, R.R., Schwarz, D., Raynor, L.R., Barron, B.J. and Webb, G.B. (2003) Al-rich diopside in alluvial ruby and corundum-bearing-bearing xenoliths, Australian and SE Asian basalt fields. Mineralogical Magazine, 67, 717732.CrossRefGoogle Scholar
Sutherland, F.L., Graham, I.T. and Webb, G.B. (2004 a) Sapphire-ruby-zircon deposits from basaltic fields, West Pacific continental margins. Pp. 385387 in: Metallogeny of the Pacific Northwest: Tectonics, Magmatism and Metallogeny of Active Continental Margins (Khanchuk, A.I., Gonevechuk, G.A., Mitrokhin, A.N., Simanenko, L.F., Cook, N.J. and Seltmann, R., editors). Dalnauka, Vladivostok, Russia.Google Scholar
Sutherland, F.L., Graham, I.T., Everard, J.L. Forsyth, S.M. and Zwingmann, H. (2004 b) Cenozoic basalts, Tasmania: Landscapes, exposures, ages, petrography, geochemistry, entrainments and petrogenesis. Field Guide A5. 17th Australian Geological Convention, Hobart, Tasmania, Geological Society of Australia, 58 pp.Google Scholar
Sutherland, F.L., Raynor, L.R. and Pogson, R.E. (2005) Table Cape vent xenolith suite, N.W. Tasmania: Mineralogy and implications for crust-mantle lithology and Miocene geotherms in Tasmania. Papers and Proceedings of the Royal Society of Tasmania, 139, 722.CrossRefGoogle Scholar
Sutthirat, C., Saminpanya, S., Droop, G.T.R., Henderson, C.M.B. and Manning, D.A.C. (2001) Clinopyroxene-corundum assemblages from alkali-basalt and alluvium, eastern Thailand: constraints on the origin of Thai rubies. Mineralogical Magazine, 65, 277295.CrossRefGoogle Scholar
Upton, B.G.J., Hinton, R.W., Aspen, P., Finch, A. and Valley, J.W. (1999) Megacrysts and associated xenoliths: evidence for migration of geochemical enriched melts in the upper mantle beneath Scotland. Journal of Petrology, 40, 935956.CrossRefGoogle Scholar
Veevers, J.J. (2001) ATLAS of Billion-year earth history of Australia and neighbours in Gondwanaland. GEMOC PRESS, Sydney, 76 pp.Google Scholar
Vysotskii, S.V., Shcheka, S.A., Nechaev, V.P., Soroka, V.P., Barkov, A.V. and Khanchuk, A.I. (2002) First finding of sapphire from Cenozoic alkali-basaltic volcanoes in the Primor'e region. Doklady Akademi Nauk CCP, Earth Science, 387A, 11001103.Google Scholar
Wathanakul, P., Atitchat, W., Pisutha-Arnond, V., Win, Tin Tin and Singbamroong, S. (2004) Evidence on the unusually high Be, Sn, Nb and Ta content in some trapiche-like sapphires from basaltic origins. 29th International Gemmological Conference, Wuhan, China. Abstracts, 114117.Google Scholar
Yim, W.W.-S., Gleadow, A.J.W. and Van Moort, J.C. (1985) Fission track dating of alluvial zircons and heavy mineral provenance in North-east Tasmania. Journal of the Geological Society of London, 142, 351356.CrossRefGoogle Scholar
Yui, Tzen-Fu, Zaw, Khin and Limtraken, P. (2003) Oxygen isotope compositions of the Denchai sapphires, Thailand: A clue to their enigmatic origin. Lithos, 67, 153161.CrossRefGoogle Scholar