SPECTROPHOTOMETRIC ANALYSIS FOR PIGMENT PALETTE IDENTIFICATION: THE CASE OF “PROFETA STANTE” Tiziana Cavaleri (Centro Conservazione e Restauro “La Venaria Reale”) Paola Croveri, Annamaria Giovagnoli (Centro Conservazione e Restauro “La Venaria Reale”) ABSTRACT A modern restoration intervention on paintings needs a preliminary investigation of constitutive materials. This investigation is important to take the proper choices before the restoration intervention and it is decisive in order to provide significant research topics. Spectrophotometric analyses have been carried out on “Profeta Stante”, a Fifteenth century oil-painted panel, in order to determine artist’s colour palette using an absolutely non-invasive method. In accordance with the principle of selective light absorption, which is the basis of spectrophotometry, the result of this analysis are reflectance spectra, the trend of which is typical of each pigment or dye. Then, the particular behaviour of a painted surface to a source emitting the visible wavelength range gives evidence of its nature and it shows how every single pigment is also characterized by the presence of other colour components that confer to it its own hue. Following the false colour infrared (IR-FC) photography outcomes, thirty measurement points, representative of the different colour present in the painting, have been chosen in order to identify the artist’s palette and also to evaluate reliability and limits of spectrophotometric and colorimetric analysis when used as preliminary investigation for pigments identification. This work as a whole aims at ensuring an exhaustive pigments comprehension by the combination of the non-invasive techniques which the Centro Conservazione e Restauro “La Venaria Reale” makes use of. The undoubted advantage is to limit the quantity of micro-sampling in accordance with the principle of minimum invasiveness. Following the adopted diagnostic protocol, when the spectrophotometric analysis were found to be insufficient for the pigments’ identification, further non-invasive analysis, such as the X-ray fluorescence (XRF), have been used to solve identification problems. 1. Introduction The Foundation “Centre for Conservation and Restoration (CCR) La Venaria Reale” hosts a graduate course of the University of Turin in Conservation and Restoration of Cultural Heritage, as well as housing a Restoration Laboratory and a Scientific Laboratory for analysis and research on materials of works of art and technology for conservation. In May 2010, the Civic Museum of Ancient Art in Palazzo Madama, in Turin, has kindly put one of its works of art, the panel painting “Profeta stante”, at the CCR’s disposal, to be studied during a graduation research work. In the most recent inventories of Palazzo Madama, this painting dates back to 1450-’60 and, by the point of view of the artistic style and technique, it’s placed in the area of the painter Jean Bapteur 1 . During the documentation phase, however, it was possible to note that the panel shows the marks of a mechanic working, as if it were planed with a mechanized machinery. For this reason the scientific investigation on the constitutive materials of the artefact has been planned, having two purposes: the identification of original and possible superimposed materials verifying the ascribed dating and the study of the conservation condition aiming to address the restoration activities. Then, since every work of art is a unique piece, the scientific investigation has been carried out through the combination of those non-invasive techniques which the Centro Conservazione e Restauro “La 1 Documents can be found in the Fondazione Torino Musei offices. The inventory number is 468/D.