In September 2012, we were invited by Finnish EPUH project group (Emeritus Professor Paavo Castren and Dr. Antero Tammisto), to continue performing field analysis using several non-invasive instruments in walls and wall paintings of the previous houses (House of Marcus Lucretius and Obonius). The study of efflorescence formation processes in walls and wall paintings of exposed and protected rooms and the factors that cause or assist the Pompeian plasters deterioration were the main objectives of the APUV expedition. For these purposes, wall and wall painting of exposed (affected by the direct impact of the rainfall, infiltration waters from the ground, etc.) and protected rooms (by roofs), and three painting panels extracted from the walls of Marcus Lucretius House more than 165 years ago and now exhibited in the Naples National Archaeological Museum (MANN) were analysed. Finally, a collection of Pompeian pigments recovered from the archaeological excavation of Pompeii and stored in their original bowls in the Naples National Archaeological Museum (MANN) was characterized by our portable analytical techniques. Three portable and hand-held instruments, Raman Spectroscopy, Diffuse Reflectance Infrared Fourier Transform (DRIFT) and hand-held energy dispersive X-ray fluorescence spectrometer (HH-ED-XRF), were selected for this expedition in order to have the molecular and the elemental characterization.
The ruins of Herculaneum, other city of Vesuvius which was buried due to the eruption of Vesuvius in 79 A.D., located on the volcanic plateau over the sea, were visited by the members of APUV expedition.
After the expedition, in our laboratories several mortar fragments excavated in 2004/2005 and several pigment samples from the MANN were analysed by Raman Spectroscopy, X-Ray Diffraction (XRD), Micro X-ray Fluorescence (m-XRF), and Scanning Electron Microscopy coupled to Energy Dispersive X-ray Spectrometry (SEM-EDS). These mortar fragments (1st, 2nd, 3rd, and 4th Pompeian painting style) had been buried for more than 2000 years.