On the provenante of the white marble of some medieval arks from S. Felice Monastery (Pavia, Italy)

The church of San Felice in Pavia was founded by the Longobard king Liutprando (712-744) and it is included in the old monastery Della Regina wanted in 771 by Ansa, wife of the last Longobard king Desiderio. It was one of the most famous monasteries of the Middle Age; now it is a building of the University of Pavia and hosts in the crypt three arks of marble, with important relics like those of St. Felice, St. Stefano, St. Giorgio and a fragment of the Holy Cross. In order to discover the provenance of the white marble of the arks, two different experimental approaches have been used. In the first, samples of the ark’s marble underwent instrumental neutron activation analysis (INAA) at the TRIGA MARK II nuclear reactor of the University of Pavia to determine Sc, Cr, Rb, Sb, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Yb, Tm, Lu, Hf, Ta, Th and U. The analytical data were inserted into the compositional database of the main white marble quarries of the Mediterranean basin (Italian Alps area: Lasa, Musso, Candoglia, Omavasso, Crevola and Vallestrona; Italian Apuan area: Massa Carrara; Turkish area: Denizli and Marmara and Greek area: Aphrodisias, Phenteli, Hymettus, Paros and Naxos) and submitted to stepwise discriminant analysis, a technique for the description and testing of inter-group differences. The procedure was able to identify those variables with the greatest discriminant power: Ce, Yb, Th, Sc and Cs. Using these variables, a cluster analysis procedure was carried out. In the second one, a destructive neutron activation analysis procedure was adopted to determine all the rare-earth elements (REE) in the samples, since, in previous papers, the discriminant power of REE to distinguish the source origin of white marble in the Mediterranean basin had been highlighted. Radiochemical separations were based on the precipitation and purification of REE fluorides. The results of the two different experimental approaches are presented, discussed and compared. Both assign the provenance of the white marble of the investigated arks to quarries of the Apuan area (Carrara)