Black gloss characterization of Greek Attic pottery carried out by means of the new non-destructive PIXE-alpha portable system

In the present work we demonstrate that the new portable system PIXE - ALPHA recently designed and realised through a collaboration between the DAMRI-SACLAY (France) and the LNS laboratory (Italy) gives the possibility of a non destructive and careful analysis of pigments and is particularly suited in the characterization of the black gloss present in Attic pottery. This because PIXE analysis, contrary to XRF, is sensitive to light elements and concerns only the surface layers; as it is known the major elements present in the black gloss range from Na to Fe. The PIXE-ALPHA system consists of a sealed 210 Po source emitting alpha particles of about 4.5 MeV; due to the above energy the analyzed dept is about 15?m and the elemental analysis is limited to the surface of the sample. The power supply and associated electronics are compact and the system is easily portable. Tests have been performed on a series of greek attic sherds exhibiting black gloss. Quantitative analysis has been performed by using GUPIX code under the very general hypothesis about the silicatic nature of the gloss and the oxide form of the constituents. The obtained concentrations agree well with the known physico-chemical destructive determinations. Results are also presented on the search for recent restoration effects in the pigments covering some ellenistic pottery from Centuripe, Sicily.