DOMUS AUREA, THE ' SALA DELLE MASCHERE': CHEMICAL AND SPECTROSCOPIC INVESTIGATIONS ON THE FRESCO PAINTINGS.

In this paper, data collected from the wall fresco paintings of room 114, called the ' Sala delle maschere', of the Domus Aurea in Rome is analysed. The chemical composition of the efflorescence is investigated by infrared spectroscopy. The colour palette is determined by means of EDXRF, Raman spectroscopy and visible reflectance spectroscopy. EDXRF has allowed an extensive mapping of the elements present in the pigments and plaster; whilst in-situ Raman spectroscopy has been determinant for attributing the molecular composition of the pigments in a number of doubtful cases. Most pigments identified are typical of Imperial Roman fresco paintings (first to fourth centuries AD) (Ward-Perkins 1981); more interestingly, we found evidence of fragments painted with Egyptian blue, which was normally used mostly in official rooms. [ABSTRACT FROM AUTHOR]