Authors: Fernando Gervilla Louis J Cabri Kari Kojonen Thomas Oberthür Thorolf W Weiser Bo Johanson Soey H Sie J L Campbell Williams J Teesdale J H Gilles Laflamme
Publish Date: 2004/04/16
Volume: 147, Issue: 3, Pages: 167-173
Abstract
The distribution of platinumgroup elements PGE in the Main Sulfide Zone of the Great Dyke of Zimbabwe in the arsenide ores of Vammala and Kylmäkoski mines in Finland and in the chromiteNi arsenide ores from the Ronda and Beni Bousera massifs Spain and Morocco has been studied by means of different optical and microanalytical techniques The results show a bimodal distribution of PGE in the ores from the Great Dyke and the Vammala and Kylmäkoski mines where Pd Pt and to lesser extent Rh occur both as discrete platinumgroup minerals and in solid solution in sulfides arsenides and sulfarsenides In the ores from Ronda and Beni Bousera platinumgroup elements occur only in solid solution in arsenides and sulfarsenidesTrace electron probe EPMA and microPIXE analyses of Pd in sulfides arsenides and sulfarsenides produce comparable results at concentration levels well above their limit of detection LOD These are 27–29 ppm by EMPA and 25–7 ppm by microPIXE Whereas trace EPMA on arsenides and sulfarsenides measure Pt concentrations above 33–35 ppm the proximity of the Pt L lines and the As Kα line severely degrade de detection limit for Pt in microPIXE analyses increasing the LOD up to 440 ppm The rest of PGE were randomly detected by both methods at concentrations close to their LOD
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