Proposal of a compositional characterization method by semi-quantitative analysis of XRF spectrum of pigments in mural painting and its application to nondestructive on-site analysis of the murals of the tomb of khonsuemheb in Egypt

To investigate the chemical compositional features of pigments used in archaeological mural paintings and paintings of art, this paper proposes a semi-quantitative analytical method involving the X-ray fluorescence spectrum obtained by nondestructive and on-site analysis. The method calculates the abundance of elements as weight per unit of area (g·cm^–2) based on the peak intensity detected on the XRF spectrum. To verify the utility of the method proposed in actual application to cultural heritage and art, we carried out nondestructive and onsite X-ray fluorescence analysis of mural paintings of the tomb of Khonsuemheb at al-Khokha Area, in Egypt using a portable X-ray fluorescence spectrometer. Our method revealed the commonality of locality of raw materials used for two different colors of earth pigments, red ocher and yellow ocher. We have confirmed that bronze (Cu-Sn alloy) of similar composition was recycled as a raw material for two synthetic pigments containing Cu, Egyptian Blue and Egyptian Green.