Imaging study of Raffaello's "La Muta" by a portable XRF spectrometer

Abstract

In studies of Cultural Heritage, there is a growing demand for methods of material investigation. X-Ray Fluorescence (XRF) analyses have proven to be essential tools in these material studies. The XRF scanning spectrometer, developed at the LABEC laboratory in Florence, can perform both elemental mapping, on areas up to 20×20cm2, and single spot analyses. Thanks to our close and long lasting collaboration with the Opificio delle Pietre Dure in Florence, one of the most prestigious restoration centers in the world, we had the opportunity to use the new XRF spectrometer in analyzing the painting "La Muta" of Raffaello Sanzio, one of the "Old Masters" of the Italian Renaissance.Beyond identification of the painting palette, the XRF study further allowed for structural analysis in cases where single spot XRF measurements would not be adequate. For example, the new system allowed us to deduce Raffaello's use of bone black pigment and to analyze various instances of "pentimenti" (underlying image in a painting, evidence of revision by the artist).