Fig. 3

P.Monts.Roca 636. Top left: the white frames highlight the three regions investigated (R1, R2 and R3). Top right: visible and NIR micro-photographs (magnification: ×50) of R1. Bottom right: XRF spectra of inked and non-inked spots from R1. Bottom right: XRF raw net peak areas of Fe measured on inked and non-inked spots in R1, R2 and R3