DETERMINATION OF PLATINUM, PALLADIUM, RUTHENIUM AND IRIDIUM IN GEOLOGICAL SAMPLES BY ISOTOPE-DILUTION INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY USING A SODIUM PEROXIDE FUSION AND TELLURIUM COPRECIPITATION

A method was developed for the determination of Ru, Pd, Ir and Pt in g eological samples by isotope dilution inductively coupled plasma mass spectrometry, After fusion of the sample with sodium peroxide, the pla tinum group elements were preconcentrated by Te coprecipitation, Resul ts obtained for the reference materials WGB-1, TDB-1, UMT-1, WPR-1, WM G-1 and SARM-7 are in excellent agreement with the recommended values for elements above the detection limit level of 0.3-2.0 ng g(-1) (whol e rock). Although the method used only 0.5 g of sample, no errors were found that could be associated with sample inhomogeneity effects in t he analysis of the above reference materials, Further measurements ind icated that the technique could be extended to the determination of Rh and Au by external calibration.