Within the context of a research program for studying with nondestructive methods the preparation and realisation techniques of mural paintings used in the Roman age, a portable ED-XRF device for elemental analysis has been set up. Preliminary tests have been carried out on two Roman mural paintings belonging to the Baia Archaeological Complex (Naples). Datable to different periods, the two paintings show different manufacturing and conservation states, thus representing a good test for verifying the
ED-XRF device capability. In situ and laboratory measurements, performed on materials of different origin and nature, have permitted the determination of the pigments and the recognition of pollution traces
