Hostname: page-component-848d4c4894-75dct Total loading time: 0 Render date: 2024-05-01T03:54:16.423Z Has data issue: false hasContentIssue false
  • English
  • Français

Kalungaite, PdAsSe, a new platinum-group mineral from the Buraco do Ouro gold mine, Cavalcante, Goiás State, Brazil

Published online by Cambridge University Press:  05 July 2018

N. F. Botelho ,
M. A. Moura ,
R. C. Peterson ,
C. J. Stanley  and
D. V. G. Silva
N. F. Botelho*
Affiliation:
Instituto de Geociências, Universidade de Brasília, DF, 70910-900 Brazil
M. A. Moura
Affiliation:
Instituto de Geociências, Universidade de Brasília, DF, 70910-900 Brazil
R. C. Peterson
Affiliation:
Department of Geological Sciences and Geological Engineering, Queen's University, Kingston, Ontario, Canada K7L 3N6
C. J. Stanley
Affiliation:
The Natural History Museum, Cromwell Road, London SW7 5BD, UK
D. V. G. Silva
Affiliation:
Instituto de Geociências, Universidade de Brasília, DF, 70910-900 Brazil
*
*E-mail: nilsonfb@unb.br
Get access Rights & Permissions [Opens in a new window]

Abstract

Kalungaite, PdAsSe, is a new mineral discovered in the Buraco do Ouro gold mine, Cavalcante town, Goiás State, Brazil. It occurs in a quartz-muscovite mylonite, related to a peraluminous granite, in platy anhedral aggregates along foliation planes. Associated ore minerals are gold, chalcopyrite, bohdanowiczite, an unnamed Pb-Bi-Se-S mineral, clausthalite, guanajuatite, stibiopalladinite, sperrylite and padmaite. Gangue minerals are muscovite, quartz and rare tourmaline and magnetite. Kalungaite is lead-grey, has a metallic lustre, a black streak and is brittle with uneven fracture. No cleavage was observed. The mineral has a micro-indentation hardness of VHN25 = 438 (range of 429–455 kg/mm2 from five indentations). Under reflected light, kalungaite is cream, or creamy grey adjacent to gold grains, has no internal reflections and is isotropic. Reflectance values in air (and in oil) are: 47.5 (33.3) at 470 nm, 46.9 (32.6) at 546 nm, 46.8 (32.6) at 589 nm and 48.0 (34.0) at 650 nm. The average of eight electron-microprobe analyses gives: Pd 41.32, As 27.49, Bi 0.35, Sb 1.59, Se 27.67 and S 1.22, total 99.64 wt. %, corresponding to Pd1.006(As0.950Sb0.034Bi0.004)Σ0.988(Se0.908S0.099)Σ1.007Kalungaite is cubic, space group Pa, a = 6.089(4) Å, V = 225.78 Å3, Z = 4. Dcalc is 7.59 g/cm3. The strongest seven X-ray powder-diffraction lines [d in Å(I)(hkl )] are: 3.027(75)(002), 1.838(100)(113), 1.172(95)(115, 333), 1.077(80)(044, 144, 334), 0.988(70)(116, 235, 253), 0.929(90)(335) and 0.918(70)(226). Kalungaite is interpreted as having formed from hydrothermal fluids of granitic origin, during syn-emplacement shearing and alteration, producing an unusual gold-platinum-group element deposit.

Keywords

KalungaitePdAsSenew mineral speciesBrazilBuraco do Ourogold deposit
Type
Research Article
Information
Mineralogical Magazine , Volume 70 , Issue 1 , February 2006 , pp. 123 - 130
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2006

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

Anthony, J.W., Bideaux, R.A., Bladh, K.W. and Nichols, M.C. (1990) Handbook of mineralogy, v.l: Elements, sulfides, sulfosalts. Mineral Data Publishing, 588 pp.Google Scholar
Altermatt, U.D. and Brown, I.D. (1987) A real-space computer-based symmetry algebra. Ada Crystallographica, A43, 125–130.Google Scholar
Botelho, N.F. and Moura, M.A. (1998) Granite-ore deposit relationship in central Brazil. Journal of South American Earth Sciences, 11, 427–438.CrossRefGoogle Scholar
Botelho, N.F. and Silva, D.V.G. (2004) Caracterização mineralógica e quimica das mineralizações de ouro (±PGE) da suíte granitíca Aurumina, Goiás. Abstracts of the XLII Congresso Brasileiro de Geologia (CD Rom).Google Scholar
Brese, N.E. and Von Schnering, H.G. (1994) Bonding trends in pyrites and a reinvestigation of the structures of PdAs2, PdSb2, PtSb2 and PtBi2 . Zeitschrift für anorganische und allgemeine Chemie, 620, 393–404.CrossRefGoogle Scholar
D'el Rey Silva, L.J.H. and Senna, V.F. (1998) Ouro em sericita-quartzo hidrotermalitos controlados por cisalhamentos conjugados brasilianos na região de Cavalcante (GO). Revista Brasileira de Geociencias, 28, 405–408.CrossRefGoogle Scholar
Jambor, J.L. and Puziewicz, J. (1993) New mineral names. American Mineralogist, 78, 451–452.Google Scholar
Marchetto, C.M.L., Larson, L.T. and Figueiredo, A.N. (1993) Platinum group minerals and gold in acid rocks, Cavalcante, Brazil. I Brazilian Meeting on Platinum Group Elements, Extended Abstracts. Brazilian Geological Society (SBG), pp. 47–51.Google Scholar
Massucato, A.J. (2003) Caracterização Estrutural do Embasamento do Grupo Aral na Zona Externa da Faixa Brasilia (GO). Unpublished PhD thesis, University of São Paulo State, Rio Claro, São Paulo, Brazil, 272 pp.Google Scholar
Mountain, B.W. and Wood, S.A. (1988) Chemical controls on the solubility, transport, and deposition of platinum and palladium in hydrothermal solutions: a thermodynamic approach. Economic Geology, 83, 492–510.CrossRefGoogle Scholar
Paar, W.H., Topa, D., Makovicky, E. and Culetto, F.J. (2005) Milotaite, PdSbSe, a new palladium mineral species from Předbořice, Czech Republic. The Canadian Mineralogist, 43,, 689–694.CrossRefGoogle Scholar
Pasava, J. (1993) Anoxic sediments – an important environment for PGE: An overview. Ore Geology Reviews, 8, 425–445.CrossRefGoogle Scholar
Pimentel, M.M., Fuck, R.A., Jost, H., Ferreira Filho, C.F. and Araújo, S.M. (2000) The basement of the Brasilia Fold Belt and the Goias Magmatic Arc. Pp. 195–230 in: Tectonic Evolution of South America (Cordani, U.G. Milani, E.J. Thomaz Filho, A. and Campos, D.A., editors). 31st International Geological Congress. Google Scholar
Simon, G., Kesler, S.E. and Essene, E.J. (1997) Phase relations among selenides, sulfides, tellurides, and oxides: II. Applications to selenide-bearing ore deposits. Economic Geology, 92, 468–484.CrossRefGoogle Scholar
Stanley, C.J. and Criddle, A.J. (1990) Precious and base metal selemde mineralization at Hope's Nose, Torquay, Devon. Mineralogical Magazine, 54, 485–493.CrossRefGoogle Scholar
Stanley, C.J., Criddle, A.J., Förster, H.-J. and Roberts, A.C. (2002) Tischendorfite, Pd8Hg3Se9, a new mineral species from Tilkerode, Harz Mountains, Germany. The Canadian Mineralogist, 40, 739–745.CrossRefGoogle Scholar
Wilde, A., Edwards, A. and Yakubchuk, A. (2003) Unconventional deposits of Pt and Pd: a review with implications for explorations. Society of Economic Geologists Newsletter, 51, 1–18.Google Scholar