The mineralogy and mineral associations of platinum group elements and gold in the Platreef at Zwartfontein, Akanani Project, Northern Bushveld Complex, South Africa

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• 作者：Frits van der Merwe (1)
  Fanus Viljoen (1) fanusv@uj.ac.za
  Mike Knoper (1)
• 刊名：Mineralogy and Petrology
• 出版年：2012
• 出版时间：September 2012
• 年：2012
• 卷：106
• 期：1-2
• 页码：25-38
• 全文大小：1,016.1 KB
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• 作者单位：1. Department of Geology, University of Johannesburg, P.O. Box 524, Auckland Park, 2006 South Africa
• ISSN：1438-1168

文摘

The mineralogy of the platinum-group elements (PGE), and gold, in the Platreef of the Bushveld Complex, was investigated using an FEI Mineral Liberation Analyser. Polished sections were prepared from 171 samples collected from two boreholes, for the in-situ examination of platinum group minerals (PGM). PGM and gold minerals encountered include maslovite (PtBiTe, 32 area% of total PGM), kotulskite (Pd(BiTe), 17 %), isoferroplatinum (Pt₃Fe, 15 %), sperrylite (PtAs₂, 11 %), cooperite (PtS, 5 %), moncheite (PtTe₂; 5 %), electrum (AuAg; 5 %), michenerite (PdBiTe; 3 %), Pd alloys (Pd, Sb, Sn; 3 %), hollingworthite ((Rh,Pt)AsS; 2 %), as well as minor (all <1 area% of total PGM) merenskyite (PdBiTe₂), laurite (RuS₂), rustenburgite (Pt_0.4Pd_0.4Sn_0.2), froodite (PdBi₂), atokite (Pd_0.5Pt_0.3Sn_0.2), stumpflite (PtSb), plumbopalladinite (Pd₃Pb₂), and zvyagintsevite (Pd₃Pb). An observed association of all PGM with base metal sulfides (BMS), and a pronounced association of PGE tellurides, arsenides and Pd&Pt alloys with secondary silicates, is consistent with the remobilisation and recrystallisation of some of the PGM’s during hydrothermal alteration and serpentinisation subsequent to their initial (primary) crystallisation from BMS (e.g. Godel et al. J Petrol 48:1569&#8211;1604, 2007; Hutchinson and McDonald Appl Earth Sci (Trans Inst Min Metall B) 114:B208&#8211;224, 2008).