Elite patronage and chromatic luxury in the Hadrianic painted ceiling of the Roman Domus “Vigna Guidi”

This study presents an archaeometric investigation of Hadrianic painted ceiling fragments from the Roman domus “Vigna Guidi” (134–138 AD) and discovered beneath the Thermae of Caracalla (Rome, Italy). Despite its exceptional preservation and artistic significance, this ceiling has remained largely unexplored from a materials science perspective. A multi-analytical approach was adopted to characterise pigments, painting techniques and stratigraphy, combining non-invasive and micro-destructive techniques: synchrotron radiation XRD, p-XRF, micro-Raman spectroscopy, colorimetry, FTIR spectroscopy, PL-OM and SEM–EDS. The palette includes high-value pigments such as cinnabar, Egyptian blue and lapis lazuli, alongside copper-based greens, natural earth pigments and carbon black, reflecting elite patronage and sophisticated chromatic control. Evidence for pigment mixtures and layered applications highlights the combined use of “a fresco” and “a secco” techniques. These results offer a robust reference dataset for comparative studies and enhance current understanding of high-status decorative practices in the Hadrianic period.