L’approvvigionamento delle tessere vitree della catacomba di S. Gennaro a Napoli in età tardoantica e altomedievale: riuso e flussi commerciali

The paper presents the results of the archaeological-archaeometric investigation of 285 mosaic tesserae, dating from the 4th to the 9th c., found in the catacombs of St. Januarius during excavations by the Pontifical Commission for Sacred Archaeology. These tesserae were found mainly on the upper level of the cemetery and in the crypt of the bishops, where the well-known arcosolia with portraits (mid-5th to mid-6th c.) are to be found. After an introduction to the in situ mosaics and the contexts in which the glass tesserae were found, which provide a chronological framework of the samples, the results of the chemical investigations carried out by combining LA-ICP-MS, SEM-EDS and Raman are discussed. The data are compared with those of 500 Italian tesserae from Rome, Ravenna, Milan, Aquileia, Padua, Vicenza, San Giusto, Faragola and Piazza Armerina, analysed by other authors.