Method of Detecting Rhenium and Tungsten in Gold Jewelry

Tungsten and rhenium doped in gold jewelry can be distinguished by their characteristic peaks using X-ray fluorescence spectroscopy. By magnifying the surface of this kind of gold jewelry samples under a metallographic microscope, multiple silver white metallographic structures were found. Following grinding and polishing, X-ray flowrescence spectra showed obvious characteristic peaks of rhenium and tungsten, which confirmed the presence of the two elements, along with other impurity elements.Standard calibration curves for rhenium and tungsten were established using inductively coupled plasma optical emission spectrometer(ICP-OES). The results showed that the recovery rates of rhenium at the test wavelength of 221.426 nm and tungsten at the test wavelengh of 239.709 nm as the analytical spectral lines were between 95% and 105%, with the relative standard deviations below 2%. During study, it was found that after uniform sampling and digestion testing, the concentrations of rhenium, tungsten, and other impurities were determined, and the difference is subtracted to obtain the gold content.