Application of energy-dispersive x-ray fluorescence to jewellery samples determining gold and silver

Abstract

The results from a study of the real scope of energy dispersive X-ray fluorescence analysis in an Assay Office, in which precious metal samples must be analysed prior to their hallmarking according to Spanish regulations, are presented. The advantages and limitations of this technique for the analysis of gold and silver jewellery samples, which is one of the most significant industrial activities in the local area (Cordoba, Spain), are reported. The results of gold and silver support the use of this technique in Assay Offices, not only for screening purposes, but also as an alternative to cupellation and potentiometric titration for a number of samples. The application of the energy-dispersive X-ray fluorencence spectrometer for the detection of plating layers like rhodium and nickel is also discussed.