An Integrated Diagnostic Approach to Deepen the Understanding of Michele di Matteo’s Wooden Panel Coronation of the Virgin

This study presents a non-invasive, integrated and multidisciplinary diagnostic approach applied to the analysis of the altarpiece Coronation of the Virgin, attributed to Michele di Matteo (15th century). The investigation focused on the evaluation of a restoration intervention carried out in 2023 using quantitative colorimetric measurements to assess chromatic variations induced by surface treatments. Other non-invasive techniques, including multispectral imaging, hyperspectral imaging, Raman spectroscopy, and visible reflectance spectroscopy, were employed to investigate the painted surface, examine underlying features, and support the characterization and spatial distribution of pictorial materials through comparison with reference standards. Finally, the proteinaceous binding media used by the artist were investigated using nano-liquid chromatography coupled with tandem mass spectrometry (nLC-MS/MS), a sensitive, high-resolution analytical approach in the field of cultural heritage studies. Overall, the integrated approach documented chromatic changes induced by cleaning, revealed the preparatory drawing and previously unknown decorative elements by infrared reflectography, and confirmed the presence of pigments previously identified in earlier studies, allowing, in some cases, for an investigation of their distribution across the painted surface. The characterization of proteinaceous binding media further contributed to a deeper understanding of the materials and techniques employed by the artist.