µ-XRF Studies on the Colour Brilliance in Ancient Wool Carpets

Figure 5

Fe K-edge XANES spectra in fluorescence yield of wool fibre dyed with FeSO₄ mordant (red) compared to Fe₂O₃ (black) and FeO (light blue) standards measured in total electron yield. The K-edge peak for the specimen is shifted towards higher photon energy compared to the FeO standard, suggesting an increase in Fe³⁺ content.