
Lapis lazuli is a blue semi-precious gemstone of the sodalite group. These rocks are characterised by the presence of clusters of golden-coloured pyrite, whose size can vary making attractive patterns on the gemstones. µ-XRF imaging can return the elemental distribution in geological samples. It enables the identification of regions of interest and, with the availability of a high-resolution X-ray guide tube, performance of detailed mapping and point analysis. In this application note, pyrite impurities and major elements distribution in a commercial lapis lazuli pendant are studied.