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Naldrettite, Pd2Sb, a new intermetallic mineral from the Mesamax Northwest deposit, Ungava region, Québec, Canada

Published online by Cambridge University Press:  05 July 2018

L. J. Cabri*
Affiliation:
Cabri Consulting Inc., 99 Fifth Avenue, Suite 122, Ottawa, Ontario, Canada K1S 5P5
A. M. McDonald
Affiliation:
Department of Earth Sciences, Laurentian University, Ramsey Lake Road, Sudbury, Ontario, Canada P3E 2C6
C. J. Stanley
Affiliation:
Natural History Museum, Cromwell Road, London SW7 5BD, UK
N. S. Rudashevsky
Affiliation:
Center for New Technologies, Roentgena Street 1, 197101, St. Petersburg, Russia
G. Poirier
Affiliation:
CANMET/MMSL, 555 Booth Street, Ottawa, Ontario, Canada K1A 0G1
B. R. Durham
Affiliation:
Canadian Royalties Inc., 1176 Delnite Road, Timmins, Ontario, Canada P4N 7J8
J. E. Mungall
Affiliation:
Department of Geology, University of Toronto, 22 Russell St., Toronto, Ontario, Canada M5S 3B1
V. N. Rudashevsky
Affiliation:
Center for New Technologies, Roentgena Street 1, 197101, St. Petersburg, Russia
*

Abstract

Naldrettite, Pd2Sb, is a new intermetallic mineral discovered in the Mesamax Northwest deposit, Cape Smith fold belt, Ungava region, northern Québec. It is associated with monoclinic pyrrhotite, pentlandite, chalcopyrite, galena, sphalerite, cobaltite, clinochlore, magnetite, sudburyite (PdSb), electrum and altaite. Other rarer associated minerals include a second new mineral (ungavaite, Pd4Sb3), sperrylite (PtAs2), michenerite (PdBiTe), petzite (Ag3AuTe4) and hessite (Ag2Te). Naldrettite occurs as anhedral grains, which are commonly attached or moulded to sulphide minerals, and also associated with clinochlore. Grains of naldrettite vary in size (equivalent circle diameter) from ~10 to 239 μm, with an average of 74.4 mm (n = 632). Cleavage was not observed and fracture is irregular. The mineral has a mean micro-indentation hardness of 393 kg/mm2. It is distinctly anisotropic, non-pleochroic, has weak bireflectance, and does not exhibit discernible internal reflections. Some grains display evidence of strain-induced polysynthetic twinning. Naldrettite appears bright creamy white in association with pentlandite, pyrrhotite, clinochlore and chalcopyrite. Reflectance values in air (and in oil) for R1 and R2 are: 49.0, 50.9 (35.9, 37.6) at 470 nm, 53.2, 55.1 (40.3, 42.1) at 546 nm, 55.4, 57.5 (42.5, 44.3) at 589 nm and 58.5, 60.1 (45.4, 47.2) at 650 nm. The average of 69 electron-microprobe analyses on 19 particles gives: Pd 63.49, Fe 0.11, Sb 35.75, As 0.31, and S 0.02, total 99.68 wt.%, corresponding to (Pd1.995Fe0.007)2.002(Sb0.982AS0.014S0.002)0.998. The mineral is orthorhombic, space group Cmc21, a 3.3906(1), b 17.5551(5), c 6.957(2) Å , V 414.097(3) Å3, Z = 8. Dcalc is 10.694(1) g/cm3. The six strongest lines in the X-ray powder-diffraction pattern [d in Å (I)(hkl)] are: 2.2454(100)(132), 2.0567(52)(043), 2.0009(40)(152), 1.2842(42)(115), 1.2122(50)(204) and 0.8584(56)(1.17.4).

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2005

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References

Bälz, U. and Schubert, K. (1969) Kristallstruktur von Pd2As (r) und Pd2Sb. Less-Common Metals, 19, 300304.CrossRefGoogle Scholar
Cabri, L.J. (1981) Unnamed platinum-group minerals. Pp. 175195 in: Platinum-Group Elements: Mineralogy, Geology, Recovery (Cabri, L.J., editor). Canadian Institute of Mining, and Metallurgy, Special Volume 23, 2nd edition, reprinted 1989.Google Scholar
Cabri, L.J. (2003) A mineralogical study of three samples from the Mesamax Northwest deposit, Cape Smith fold belt, Northern Quebec, for Canadian Royalties Inc. Confidential Report 2003-08, 87 pp.Google Scholar
Cabri, L.J. (2004) New developments in process mineralogy of platinum-bearing ores. Proceedings of the Canadian Mineral Processors 36th annual meeting, pp. 189198.Google Scholar
Fleischer, M., Chao, G.Y. and Cabri, L.J. (1975) New mineral names. American Mineralogist, 60, 736739.Google Scholar
Fleischer, M., Pabst, A., Mandarino, J.A., Chao, G.Y. and Cabri, L.J. (1976) New Mineral names. American Mineralogist, 61, 174186.Google Scholar
Jen, Y.-C. and Huang, W.-K. (1973) On some new minerals and varieties of the platinum-group elements. Geochimica, 1, 2330.(in Chinese).Google Scholar
Kim, W.S. and Chao, G.Y. (1996) Phase relations in the system Pd-Pt-Sb. Neues Jahrbuch für Mineralogie Monatshefte, 8, 351364.Google Scholar
McDonald, A.M., Cabri, L.J., Stanley, C.J., Rudashevsky, N.S., Poirier, G., Ross, K.C., Mungall, J.E., Durham, B.R. and Rudashevsky, V.N. Ungavaite, Pd4Sb3, a new intermetallic mineral from the Mesamax Northwest deposit, Ungava region, Québec, Canada: Description and genetic implications. The Canadian Mineralogist (submitted).Google Scholar
Nolze, G. and Krauss, W. (1998) Powdercell, v. 2.3. Federal Institute for Materials Research and Testing, Berlin, Germany.Google Scholar
Rudashevsky, N.S., Lupal, S.D. and Rudashevsky, V.N. (2001) The hydraulic classifier. Russia patent N 2165300. Patent Cooperation Treaty PCT/ RU01/ 00123 (Moscow: 20 April 2001; 10 May 2001) (in Russian and English).Google Scholar
Rudashevsky, N.S., Garutti, G., Andersen, J.C.ø., Kretser, Y.L., Rudashevsky, V.N. and Zaccarini, F. (2002) Separation of accessory minerals from rocks and ores by hydroseparation (HS) technology: method and application to CHR-2 chromitite,CrossRefGoogle Scholar
Niquelândia, Brazil. Transactions, Institution of Mining and Metallurgy/ Proceedings of the Australasian Institute of Mining and Metallurgy, Section B: Applied Earth Science, 111, 8794.Google Scholar
Rudashevsky, N.S., Kreteer, Y.L., Orseov, D.A. and Rudashevsky, V.N. (2003) Palladium-platinum mineralization in copper-nickel vein ores in the Ioko-Dovyren layered massif. Doklady Earth Sciences, 391A, 858861.Google 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, 739745.CrossRefGoogle Scholar