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An unusual ruby-sapphire-sapphirine-spinel assemblage from the Tertiary Barrington volcanic province, New South Wales, Australia

Published online by Cambridge University Press:  05 July 2018

F. Lin Sutherland
Affiliation:
Mineralogy and Petrology Section, Australian Museum, 6 College Street, Sydney, N.S.W. 2000, Australia
Robert R. Coenraads
Affiliation:
Gemmological Association of Australia (N.S.W. Division), 24 Wentworth Avenue, Sydney, N.S.W. 2000, Australia

Abstract

Ruby-sapphire-sapphirine-spinel forms small, corroded, crystalline aggregates in corundum bearing alluvials shed from the Tertiary Barrington basalt shield volcano. Sapphirine is near a 7:9:3 (MgO-Al2O3-SiO2) composition and, together with the corundum, shows reaction rims of pleonaste spinel. Spinel in the aggregates has a compositional range Sp 68–73 Hc 27–29 Cm 0–3. The aggregates give new insights into the ruby-sapphire source rocks. Potential origins include metamorphic recrystallization of aluminous material (below 1460°C) or high temperature-high pressure crystallization reactions related to lamprophyric or basaltic magmas (up to 1300°C and 20 kbar). Sapphirine-spinel thermometry suggests final crystallization temperatures for the aggregates around 780 to 940°C and reaction with host magmas at over 1000°C.

The Barrington gemfield includes two distinct corundum suites. One, typical in eastern Australia, is dominated by blue-green, well-crystallized, growth-zoned sapphire, commonly containing rutile silk and Ferich spinel inclusions (Hc 51–73, Mt 18–35, Mf 6–8, Usp 2–6). The other, an unusual suite, is dominated by ruby and pastel coloured sapphires, with little crystal shape or growth zonation and restricted mineral inclusions, mostly chromian pleonaste and pleonaste. The ruby-sapphire-sapphirine-spinel aggregates provoke new thoughts on the origin of rubies and sapphires and their indicator minerals in eastern Australian and southeastern Asian volcanic gemfields.

Type
Mineralogy
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1996

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References

Barker, F. (1964) Reaction between mafic magmas and pelitic schist, Cortlandt, New York. Amer. J. Sci., 262, 614–34.CrossRefGoogle Scholar
Berrange, J.P. and Jobbins, E.A. (1976) The Geology, Gemmology, Mining Methods and Economic Potential of the Pailin Ruby and Sapphire Gem- field, Khmer Republic. Inst. Geol. Sci., Overseas Div. Rep., 35, 32 pp.Google Scholar
Bertrand, P., Ellis, D.J. and Green, D.H. (1991) The stability of sapphirine-quartz and hypersthene- sillimanite-quartz assemblages: an experimental investigation in the system FeO-MgO-Al2O3-SiO2 under H2O and CO2 conditions. Contrib. Mineral Petrol., 108, 5571.CrossRefGoogle Scholar
Bishop, F.C. and Newton, R.C. (1975) The composition of low-pressure synthetic sapphirine. J. Geol., 83, 511–7.CrossRefGoogle Scholar
Coenraads, R.R. (1990) Key areas for alluvial diamond and sapphire exploration in the New England gem fields, New South Wales, Australia. Econ. Geol., 85, 1186–207.CrossRefGoogle Scholar
Coenraads, R.R. (1992) Sapphires and rubies associated with volcanic provinces: inclusions and surface features shed light on their origin. Austral. Gemmol, 18(3), 70 78.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. Mineral. Mag., 54, 113–22.CrossRefGoogle Scholar
Coenraads, R.R., Vichit, P. and Sutherland, F.L. (1995) An unusual sapphire-zircon-magnetite xenolith from the Chanthaburi Gem Province, Thailand. Mineral. Mag., 59, 465–79.CrossRefGoogle Scholar
Coldham, T. (1985) Sapphires from Australia. Gems & Gemology 21, 130-46.CrossRefGoogle Scholar
Collins, W.J., Offler, R., Farrell, J.R. and Landenberger, B. (1993) A revised Late Palaeozoic-Early Mesozoic tectonic history for the southern New England Fold Belt. In New England Orogen, eastern Australia (Flood, P.G. and Aitchison, J.C., eds.), Dept. Geol. Geophys., Univ. New England, Armidale, N.S.W., pp 6984.Google Scholar
Deer, W.A., Howie, R.A. and Zussman, J. (1978) RockForming Minerals Single-Chain Silicates Volume 2A Second Edition, Longman Group, London, 668 pp.Google Scholar
Droop, G.T.R. (1987) A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analyses, using stoichiometric criteria. Mineral. Mag., 51, 431 5.CrossRefGoogle Scholar
Eggins, S. and Hensen, B.J. (1987) Evolution of mantle- derived, augite-hypersthene granodiorites by crystal- liquid fractionation: Barrington Tops Batholith, eastern Australia. Lithos, 20, 295 310.CrossRefGoogle Scholar
Fisk, M.R. and Ford, C.E. (1984) Melting of Mauritius Island intermediate series lava. Progress Exp. Petrol. (N.E.R.C.). 6, 114-8.Google Scholar
Griffin, W.L. and O'Reilly, S.Y. (1986) Sapphirine in a mantle-derived xenolith from Delegate, Australia. Mineral Mag., 50, 635 40.CrossRefGoogle Scholar
Giibelin, E.J. and Koivula, J.I. (1986) Photo atlas of inclusions in gemstones, ABC Edition, Zurich, 531 pp.Google Scholar
Guo, J.F., O'Reilly, S.Y. and Griffin, W.L. (1992a) Origin of sapphire in eastern Australian basalts: Inferred from inclusion studies. Geol. Soc. Austral. Abstr. Ser., 32, 219 20.Google Scholar
Guo, J., Wang, F. and Yakoumelos, G. (1992^) Sapphires from Changle in Shandong Province, China. Gems Gemology, 28, 255 60.Google Scholar
Hensen, B.J. (1986) Theoretical phase relations involving cordierite and garnet revisited: the influence of oxygen fugacity on the stability of sapphirine and spinel in the system Mg-Fe-Al-Si-O. Contrib. Mineral. Petrol, 92, 362 7.CrossRefGoogle Scholar
Hughes, R.W. (1990) Corundum Butterworth-Heinemann, London, 314 pp.Google Scholar
Jobbins, E.A. and Berrange, J.P. (1981) The Pailin ruby and sapphire gemfleld, Cambodia. J. GemmoL, 17, 555.Google Scholar
Johnson, R.W., compl. and ed. (1989) Intraplate Volcanism in Eastern Australia and New Zealand Cambridge University Press, Cambridge, 408 pp.Google Scholar
Keller, P.C. (1990) Gemstones and their Origins Van Nostrand Reinhold, New York, 144 pp.CrossRefGoogle Scholar
Keller, P.C. (1992) Gemstones of East Africa Geoscience Press, Phoenix, Arizona, 144 pp.Google Scholar
Kimbrough, D.L., Cross, K.C. and Korsch, RJ. (1993) U-Pb isotopic ages for zircons from the Pola Fogal and Nundle granite suites, southern New England Orogen. In: New England Orogen, eastern Australia (P.G. Flood and J.C. Aitchison, eds), Dept. Geol. Geophys., Univ. New England, Armidale, N.S.W., 403-12.Google Scholar
Koivula, J.I. and Fryer, C.W. (1987) Sapphirine (not sapphire) in a ruby from Bo Rai, Thailand. J. GemmoL, 20, 369-70.CrossRefGoogle Scholar
Levinson, A.A. and Cook, F.A. (1995) Gem corundum in alkali basalt: Origin and occurrence. Gems Gemology, 30, 253-62.CrossRefGoogle Scholar
Lindsley, D.H. (1976) Experimental studies of oxide minerals. In: Oxide Minerals(Rumble, D. ed.), Res. Mineral., Mineral. Soc. Am., vol 3, 6188.CrossRefGoogle Scholar
Liu, T-C. and Presnall, D.C. (1990) Liquidus phase relationships on the join anorthite-forsterite-quartz at 20 kbar with applications to basalt petrogenesis and igneous sapphirine. Contrib. Mineral. Petrol, 104, 735–42.CrossRefGoogle Scholar
MacNevin, A.A. (1977) Diamonds in New South Wales. Dept. Min. Geol. Surv. NSW. Miner. Resour., 42, 125 PP.Google Scholar
MacNevin, A.A. and Holmes, G.G. (1980) Gemstones. Geol. Surv. NSW., Miner. Indus. N.S.W., 18, 119 pp.Google Scholar
Mason, D.R. (1982) Stratigraphy of western parts of the Barrington Tops Tertiary volcanic field. In: New England Geology, A. H. Voisey Symposium (Flood, P.G. and Runnegar, B., eds), Dept. Geol. Univ. New England A. H. V. Club, Armidale, N.S.W., 133-9.Google Scholar
Mason, D.R. (1989) Barrington. In: Intraplate Volcanism in eastern Australia and New Zealand(Johnson, R.W., compl. and ed.), Cambridge University Press, Cambridge, 123-4.Google Scholar
McBirney, A.R. and Hunter, R.H. (1995) The cumulate paradigm reconsidered. J. Geology, 103, 114–22.CrossRefGoogle Scholar
Mountain, E.D. (1939) Sapphirine crystals from Blinkwater, Transvaal. Mineral. Mag., 25, 277-82.Google Scholar
Oliver, G.J. and Townsend, IJ. (1993) Gemstones in AustraliaAustralian Gemstone Industry Council, 72 pp. Australian Government Publishing Service, Canberra.Google Scholar
O'Reilly, S.Y., Griffin, W.L. and Stabel, A. (1988) Evolution of Phanerozoic eastern Australia: isotopic evidence for magmatic and tectonic underplating. In: Oceanic and Continental Lithosphere: Similarities and Differences (M.A. Menzies and K.G. Cox, eds). J. Petrol-Special PubL, 89 108.Google Scholar
Owen, J.V. and Greenough, J.D. (1991) An empirical sapphirine-spinel Mg-Fe exchange thermometer and its application to high grade xenoliths in the Pope Harbour dyke, Nova Scotia, Canada. Lithos 26, 317-32.CrossRefGoogle Scholar
Pain, C.F. (1983) Geomorphology of the Barrington Tops area, New South Wales. J. Geol. Soc. Austral, 30, 187 -94.CrossRefGoogle Scholar
Robertson, A.D. and Sutherland, F.L. (1992) Possible origins and ages for sapphire and diamonds from the Central Queensland gemfields. In: R. O. Chalmers Commemorative Papers (Mineralogy, Meteorites, Geology) (F.L, Sutherland, ed). Rec. Austral. Museum SuppL, 15, 45 54.Google Scholar
Rock, N.M.S. (1991) Lamprohyres Van Nostrand Reinhold, New York, USA, 285 pp.Google Scholar
Smart, R.M. and Glasser, F.P. (1976) Phase relationships of cordierite and sapphirine in ttie system MgO- Al2O3 SiO2. J. Mater. ScL, 11, 1459 64.Google Scholar
Stephenson, P.J. (1990) The geological context of sapphire occurrences in the Anakie region, central Queensland. Geol. Soc. Austral. Abstr. Ser., 25, 232–3.Google Scholar
Sutherland, F.L. (1985) Regional controls in Eastern Australian volcanism. In: Volcanism in Eastern Australia with case histories from New South Wales (Sutherland, F.L., Franklin, B.J. and Waltho, A.E., eds), Geol. Soc. Austral., New South Wales Div. PubL, 1, 1331.Google Scholar
Sutherland, F.L. (1991) Gemstones of the Southern Continents Reed Books, Sydney, 256 pp.Google Scholar
Sutherland, F.L. and Wellman, P. (1986) Potassium- argon ages of Tertiary volcanic rocks, Tasmania. Pap. Proc. Roy. Soc. Tasm., 120, 77 86.Google Scholar
Sutherland, F.L. Barron, B.J. and Webb, G. B. (1993a) Barrington volcano-repeated gemstone eruptions (zircon, sapphire and ruby) at the edge of the Sydney Basin. Adv. Stud. Syd. Bas., 26th Newcastle Symp. Proc., 137 44.Google Scholar
Sutherland, F.L., Pogson, R.E. and Hollis, J.D. (1993b) Growth of the central New England basaltic gemfields, New South Wales, based on zircon fission track dating. In: New England Orogen, eastern Australia (Flood, P.G. and Aitchison, J.C., eds), Dept. Geol. Geophys. Univ. New England, Armidale, N.S.W., 483-91.Google Scholar
Taylor, H.C.J. (1973) Melting relations in the system MgO-Al2O3-SiO2 at 15 kb. Bull. Geol. Soc. Amer.y 84, 1335-48.2.0.CO;2>CrossRefGoogle Scholar
Vernon, R.H. (1970) Comparative grain-boundary studies of some basic and ultrabasic granulites, nodules and cumulates. Scottish J. Geol., 6, 337-51.CrossRefGoogle Scholar
Vichit, P. (1992) Gemstones in Thailand. In: Proceedings of the National Conference on "Geologic Resources of Thailand: Potential for Future Development(Piencharoen, C., ed. in chief), Dept. Mineral Resources, Bangkok, Thailand, 124-50.Google Scholar
Wellman, P. (1989) Upper Mantle, Crust and Geophysical Volcanology of Eastern Australia. In: Intraplate Volcanism in Eastern Australia and New Zealand(Johnson, R. W., compl. and ed.), Cambridge University Press, Cambridge, 2938.Google Scholar
Wellman, P. and McDougall, I. (1974) Potassium-argon ages of the Cainozoic volcanic rocks of New South Wales, Australia. Geol. Soc. Austral., 21, 247-72.CrossRefGoogle Scholar