AR-XRF measurements and data treatment for the evaluation of gildings samples in the Cultural Heritage

Angle resolved XRF (AR-XRF) is an analytical technique in which the sample is analyzed at different angles of detection or irradiation. The change in the geometry affects the intensity of the elemental characteristic emission from the sample, which depends on the in-depth distribution of analyte. In this paper, for the first time, we apply AR-XRF to gilding samples that mime real cultural heritage ones. The samples analysed, also investigated with scanning electron microscopy, present small lateral inhomogeneities and a rough surface. Moreover, we illustrate how to analyze AR-XRF data, from the collection of XRF spectra to the creation of AR-XRF profiles and the fitting of data using Sherman's equation. Using AR-XRF combined with the fundamental parameters method we calculate the massive thickness of laboratory made layered samples.