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The ED-XRF analysis technique is becoming increasingly popular in the jewelry industry. The possibility of very quickly determining the composition of a finished object of even complex shape without destroying or ruining it, is of unique appeal compared to other more conventional techniques (e.g. ICP or cupping). However, this technique has so far been relegated to a generally marginal role limited to verifying the raw composition due to the perception that this type of measurement is inaccurate when used to measure the precious metal content of the object. In view of the recent publication of the ISO 23345 standard, which deals precisely with analyzing fineness using ED-XRF benchtop instruments, Progold has focused on investigating the peculiarities and potential of this technique. Over the course of several months, the Progold laboratory explored how the analysis can be influenced by factors such as the structure of samples, the collimator used for measurement, the composition declared during calibration, and finally managed to outline a series of indications that, together with the ISO standard, can guarantee excellent results during analysis. Progold's research has been able to confirm that the use of ED-XRF to measure the fineness of gold in jewelry is possible, at least for elements whose nominal composition is known and where the instrument can be calibrated with suitable reference standards, with the possibility of achieving levels of accuracy, under certain conditions, comparable to those of cupellation. In the jewelry sector, increasing attention is being paid to controlling the production cycle in order to quickly intercept possible problems and make all production more efficient. This clearly calls for an increasing number of analyses, including on semi-finished products, and the ED-XRF technique, if correctly applied, could then be the answer to this need.