Unveiling the paint stratigraphy and technique of Roman African polychrome statues

If ancient written sources and the visual analysis of polychromies have recently revealed the complexity of the technique of painting on statues and their frequent restoration, the non-invasive punctual chemical analyses carried out do not allow one to access the chemical composition of the different paint layers. This paper presents the analysis of three statues from Roman Africa discussing the results obtained from this understudied territory and chronology. By combining visual observation (VIS, UVL), video microscopy and MA-XRF imaging, we propose here a non-invasive protocol to determine the chemical composition of the different paint layers. This allows one to unveil the complexity of the 'know-how' of a sculpture painter and sheds light on the evolution of the original appearance of the statues.