Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-24T12:20:54.865Z Has data issue: false hasContentIssue false

Phases in the Ni–Sb–As system which occur in the Bon Accord oxide body, Barberton greenstone belt, South Africa

Published online by Cambridge University Press:  02 January 2018

M. Tredoux*
Affiliation:
Department of Geology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
F. Zaccarini
Affiliation:
Department of Applied Geosciences and Geophysics, University of Leoben, Peter Tunner Str. 5, A-8700 Leoben, Austria
G. Garuti
Affiliation:
Department of Applied Geosciences and Geophysics, University of Leoben, Peter Tunner Str. 5, A-8700 Leoben, Austria
D. E. Miller
Affiliation:
Department of Geology, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
*

Abstract

An oxide-silicate occurrence, containing >40 wt.% NiO whole rock and showing enrichment in the platinum-group elements and antimony, was investigated at high magnification. Many phases with grain sizes generally <100 μm were observed; electron microprobe analysis indicated that, although some of these are known minerals in Ni–Sb–As space (such as breithauptite and orcelite), most of them cluster around the following compositions: Ni3Sb, Ni3(Sb,As), Ni3As, Ni5(Sb,As)2, Ni7(Sb,As)3 and Ni11(Sb,As)8. Such phases have been observed in synthetic systems, but up to now not in nature. The data reported here therefore probably represent the compositions of new minerals.

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

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.)

References

Bayliss, P. (2001) Dienerite - a mystification. Mineralogical Magazine, 65, 685687.CrossRefGoogle Scholar
Bindi, L., Tredoux, M., Zaccarini, F., Miller, D.E. and Garuti, G. (2014) Non-stoichiometric nickel arsenides in nature: The structure of orcelite, Ni5_xAs2 (x = 0.25), from the Bon Accord oxide body, South Africa. Journal of Alloys and Compounds, 601,175178 CrossRefGoogle Scholar
Crosse, A.F. (1921) A rich nickel ore. Journal of the Chemical Society of South Africa, 21, 126.Google Scholar
De Waal, S.A. (1972) Nickel minerals from Barberton, South Africa: V: Trevorite, redescribed. American Mineralogist, 57, 15241527. Google Scholar
De Waal, S.A. (1978) The nickel deposit at Bon Accord, Barberton, South Africa - A proposed paleometeorite. Pp. 8798 in: Mineralisation in metamorphic terranes (W.J. Verwoerd, editor). Special Publication, Geological Society of South Africa, Johannesburg, South Africa.Google Scholar
De Waal, S.A. (1979) The metamorphism of the Bon Accord nickel deposit by the Nelspruit granite. Transactions of the Geological Society of South Africa, 82, 335342. Google Scholar
De Waal, S.A. and Calk, L.C. (1973) Nickel minerals from Barberton, South Africa: VI: Liebenbergite, a nickel olivine. American Mineralogist, 58, 733735..Google Scholar
De Wit, M.J., Hart, R.A. and Hart, R.J. (1987) The Jamestown ophiolite complex, Barberton Mountain Land: A composite section through 3.5 Ga simatic lithosphere. Journal of African Earth Sciences, 6, 681730. CrossRefGoogle Scholar
Helmy, H.M., Ballhaus, C., Fonseca, R.O.C.., Wirth, R., Nagel, T. and Tredoux, M. (2013) Noble metal nanoclusters and nanophases precede mineral formation inmagmatic sulphide melts. Nature Communication, 4, 2405, http://dx.doi:10.1038/ncomms3405 CrossRefGoogle ScholarPubMed
O'Driscoll, B., Clay, P.L., Lenaz, D., Cawthorn, R.G., Adetunji, J. and Kronz, A. (2014) Trevorite: Ni-rich spinel formed by metasomatism and desulphurisation processes at Bon Accord, South Africa. Mineralogical Magazine, 78, 145163. CrossRefGoogle Scholar
Okamoto, H. (2009) Ni-Sb (Nickel-Antimony). Journal of Phase Equilibria and Diffusion, 30,301302 CrossRefGoogle Scholar
Partridge, F.C. (1944) Trevorite and a suggested new nickel-bearing silicate from Bon Accord, Sheba Siding, Barberton district. Transactions of the Geological Society of South Africa, 46, 119126. Google Scholar
Raghavan, V (2004) Fe-Ni-Sb (Iron-Nickel-Antimony). Journal of Phase Equilibria and Diffusion, 25, 553.CrossRefGoogle Scholar
Tredoux, M., de Wit, Ml, Hart, R.J., Armstrong, R.A., Lindsay, N.M. and Sellschop, J.P.F.. (1989) Platinum group elements in a 3.5 Ga nickel-iron occurrence, Possible evidence of a deep mantle origin. Journal of Geophysical Research, 94(B1), 795813.CrossRefGoogle Scholar
Tredoux, M., Roelofse, F. and Shukolyukov, A. (2014) A Cr isotopic study of the Bon Accord NiO body, Barberton greenstone belt, South Africa. Chemical Geology, 390,182190 CrossRefGoogle Scholar
Trevor, T.G. (1920) Nickel: Notes on the occurrence in the Barberton district. South African Journal of Industry, 3, 532533. Google Scholar
Walker, T.L. (1923) Trevorite a distinct mineral species. University of Toronto Studies, 16, 53.Google Scholar
Wildau, A. (2012) An investigation of microscopic phases in the Bon Accord Ni-oxide body, Barberton region, South Africa. Unpublished M.Sc. dissertation. University of the Free State, Bloemfontein, South Africa.Google Scholar
Zaccarini, F., Tredoux, M., Miller, D.E., Garuti, G., Aiglsperger, T and Proenza, J.A. (2014) The occur-rence of platinum-group and gold minerals in the Bon Accord Ni-oxide body, South Africa. American Mineralogist, 99,17741782 CrossRefGoogle Scholar
Supplementary material: File

Tredoux et al. supplementary material

Supplementary Material

Download Tredoux et al. supplementary material(File)
File 50.7 KB