platinum mineralization of the great dyke, zimbabwe

SESSION 7. NEW ADVANCES IN THE UNDERSTANDING OF PGE MINERALOGY FROM MAGMATIC TO SUPERGENE ENVIRONMENTS
271
PLATINUM MINERALIZATION OF THE GREAT DYKE,
ZIMBABWE, AND THE BUSHVELD COMPLEX, SOUTH
AFRICA – THE FATE OF PGM FROM SULFIDE ORES VIA THE
WEATHERING CYCLE (OXIDIZED ORES) INTO PLACERS
Oberthür, T.1, Melcher, F.2, Locmelis, M.3, Weiser, T.W.1 & Junge, M.1
1
Bundesanstalt für Geowissenschaften und Rohstoffe (BGR), Stilleweg 2, D-30655 Hannover, Germany
2
Dept. Geowissenschaften, Montanuniversität Leoben, Peter Tunner Str. 5, A-8700 Leoben, Austria
3
Centre for Exploration Targeting, The University of Western Australia, 6009 Crawley, Australia
e-mail: [email protected]
ABSTRACT. The world’s prime sources of metallurgical chromite and platinum-group elements (PGE) are
layered intrusions of Proterozoic and Archean age (e.g. the Bushveld Complex, South Africa; the Great Dyke,
Zimbabwe; and the Stillwater Complex, USA). This contribution summarizes previous studies of our working
group on pristine and oxidized platinum-group element (PGE) ores as well as related placer accumulations on
the Great Dyke and the Bushveld Complex.
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Fig. 1. Assemblage of sulfides (cpy, pn, mil, py) and various PGM
(moncheite, braggite, malanite, kotulskite and temagamite)
in the UG-2. Lebowa Mine (AS 7631), reflected light, in oil
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12-TH INTERNATIONAL PLATINUM SYMPOSIUM
REFERENCES
Fig. 2. BSE image of eluvial Pt-Fe alloy grain (4-59),
Onverwacht Pipe downslope
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