Organic materials in the wall paintings in Pompei: a case study of Insula del Centenario

BACKGROUND: The present research concerns the Roman wall paintings preserved at Insula del Centenario (IX, 8), the important Pompeian block situated in the Regio IX, along Via di Nola. RESULTS: The aims of this research are two: to verify the presence of lipidic and proteinaceous material to spread the pigments, and to identify organic matter in painting materials owing to previous restoration works. The samples collected from the wall paintings of different rooms have been investigated by Fourier Transform Infrared Spectroscopy (FT-IR), and Gas Chromatography/ Mass Spectrometry (GC/MS). CONCLUSIONS: The analytical results show that these Roman wall paintings were realized without the use of lipidic and proteinaceous materials, supposedly in fresco technique. Moreover, it was detected that wax, egg, and animal glue were used in previous restoration works for protective purpose and to restore the wall paintings to their original brilliant colours.