Nondestructive determination of allergenic and toxic elements in jewelry: a comparison of benchtop and portable energy dispersive X-ray fluorescence spectrometers

摘要

X-ray fluorescence (XRF) is a widespread technique for alloy characterization and nowadays portable instruments are becoming popular. The objective of this study was to analyze necklaces, earrings, bracelets, rings and piercings by portable and benchtop XRF equipments, in order to verify if the presented methodology allows characterization of these objects, determining whether they meet - or not - current legislations regarding the concentrations of metals. Also to compare the equipments and check the feasibility of field measurements with portable equipments in just 5 s of analysis. In total 117 pieces were analyzed, surpassing 450 measurements. Nickel and Pb were found over the established limit in several samples, even on those attested as Ni- and Pb-free. It was possible to verify contents of noble or allergenic metals, with adequate detectability, low deviation and good agreement between both equipments employed, without sample treatment steps and without residue generation.