“Monochromes on marble” from Pompeii and Herculaneum: new researches

This is a new step in the research about “monochromes on marbles”, twelve painted marble slabs from Pompeii, Herculaneum and maybe Rome, now in the Museo Archeologico Nazionale in Naples and in the Kunsthistorisches Museum in Vienna. These marble pinakes were set in walls of roman buildings with iron clamps. The scenes are of different subjects spanning from mythological to athletic ones. Their name, Monochromes, was chosen during the Bourbonic period due to the red colour visible on the surface, but actually the slabs show also green, yellow, brown and black pigments, still visible to the naked eye. The paper shows the preliminary results obtained by means of transportable, noninvasive techniques employed for the analysis of the ten slabs in Naples. The employed techniques can be divided in two groups: i) imaging (Ultraviolet reflected photography, Ultraviolet fluorescence photography, Ultraviolet false colour, Near Infrared photography, Infrared false colour, Visible Induced Luminescence) and ii) single spot (X-ray fluorescence spectroscopy, Fiber Optics Reflectance Spectroscopy in UV-VIS); Portable Optical Microscopy was used for documenting the analysed areas. Crossing the visual results obtained with imaging techniques with data analyses some new information about drawings, pigments and conservation history have been provided, in order to deepen the knowledge of this rare kind of archaeological finds.