Pigmenti, lacche e coloranti: sviluppo e messa a punto di protocolli di indagine spettroscopica per lo studio di manufatti di interesse storico-artistico e archeologico

The present research project aims to develop innovative non-invasive protocols that effectively integrate the traditional spectroscopic methods used for the analysis of decorated surfaces, based on the outcomes on real-world case studies experimentation, in order to identify reliable and optimized strategies that simplify and codify the analytical work, making it applicable to related artworks. To this end, micro-Raman, fiber-optic reflectance, X-ray fluorescence, and infrared spectroscopies were examined, supplemented by the use of digital microscopy. By exclusively using portable instrumentation, these techniques were extensively applied to two case studies representative of two types of painted artefacts: medieval illumination on parchment and Roman painted plasters. In particular, the decoration of a precious illuminated Psalter of the late 13th century (ms. 353, Biblioteca Antica del Seminario Vescovile, Padua) and the decoration of fragmentary painted plasters from the deposit of the Sarno Baths (Pompeii) were examined. The potentials and limitations of the different portable techniques, as well as the efficacy of their integration, were assessed. Noninvasive, integrated multi-technique protocols were developed, evaluated, and proposed to optimize the information available in situ for these kinds of pictorial surfaces.