Non destructive quantitative XRF analysis on greek archaic pottery of the Alaimo Santuary in Lentini (Sicily)

The deposit of the Alaimo's Sanctuary in Lentini has yielded a large amount of Greek pottery of the protoarchaic period. A typological study performed on the finds, has distinguished three different classes of materials (Corinthian, Local and East Greek pottery). In order to group the finds and to identify local imitations of imported goods, 42 sherds of different pottery shapes have been analysed by means of the non destructive XRF technique. Measurements have been performed by using a portable XRF system entirely designed and realised at the LNS/INFN LANDIS laboratory of Catania (Italy). It consists of a Si(Li) detector coupled to a measurement head containing three 109Cd radioactive sources and three 55Fe sources arranged in an annular geometry. One set of sources can be selected with a simple rotating device. Measurements have been performed by using the 109Cd radioactive sources. The 109Cd X-rays are particularly suitable to excite some important trace elements like Rb, Sr, Y, Zr and Nb as well as some matrix elements like Ca and Fe. The absolute concentration of Rb, Sr, Y, Zr and Nb has been determined by means of a method based, through a multi-linear regression approach, on the existing relation between the net fluorescence counts and the concentration. A multivariate cluster analysis on compositional data has been finally performed; the 42 samples resulted clustered in three defined class. At this stage a petrological-chemical analysis, limited to only a few samples, will help us to establish the provenance of some doubtful finds.