PIXE and pXRF Comparison Analysis of a Mockup Canvas Painting

For the purposes of comparison among different equipments and laboratories involved in atomic-nuclear methodologies applied in arts and archaeometry, a special mockup canvas painting was made with dozens of pigments of different colors and varnishes of different types and manufacturers. This study evaluate two different XRF equipment and PIXE methods as complementary tools to examine canvas paintings. Twenty-four inorganic substances of this mockup canvas were measured in three different laboratories, LEC, LFNA, and LAMFI for the identification of the key elements. In this paper, net count ratios and standard percentage deviations between lines are shown, as well as examples of sensibility to low-content elements that can be used for distinguishing pigments, and a comparison of the penetration of these techniques. The results show the differences between the pXRF and PIXE methodologies and between the two pXRF geometry/equipments employed.