The Geology, Geochemistry, Mineralogy and Mineral Beneficiation of Platinum-Group Elements. CIM Special Volume 54

摘要

In the 20 years that have passed since the first Cabri volume on PGE, the price of palladium has increased from one-fourth to three times that of gold, and has then fallen back to near price equivalency. The rapid increase sparked a period of major worldwide exploration that, after follow-up research, has resulted in an explosion in our knowledge about PGE deposits. This present volume is not only a welcome update on the fall-out from this explosion, but an encyclopedia on these deposits. The first chapter, by Hoffman and Dunn, is concerned with sample preparation and bulk analytical techniques. The authors provide a very useful comparison of the Pb and NiS fire assay techniques coupled with both ICP-OES and ICP-MS finishes. The Pb fire assay technique using a silver dore bead is unsuitable for Rh and Ir, but when coupled with an ICP-MS finish, provides detection limits that are equal to or better than NiS fire assay with the same finish. The NiS fire assay method concentrates all of the noble metals; with this technique an INAA finish gives better detection limits for Au, Rh, and Ir than ICP-MS, whereas the latter is significantly better for Pd, Pt, and Ru. The authors comment on recent so-called "desert dirt" scams, pointing out that interferences associated with the Fe ingot technique when coupled with the ICP-OES or DCP-OES finishes that are normally used by the "certified" analysts employed in these cases render the results worthless. For example, the authors calculate that a U.S. nickel coin, when analyzed in this way and not corrected for interferences, appears to contain enough Pt, Pd, Rh, and Ir to give it an inherent value of 15.00 dollars!