Petrographic characterization and provenance determination of the crystalline marbles used in the Roman city of Banasa (Morocco): New data on the import of Iberian marble in Roman North Africa.

This paper reports the results of an archaeometric study of the crystalline marbles used in the Roman city of Banasa (Morocco). On-site surveys allowed a detailed inspection of the monuments of the ancient city and sampling of the different marble lithotypes used for architectural purposes and sculptures. The inventory was completed by the study of both the grey-and-white streaked or spotted marble items stored in the warehouse of the archaeological site and of those currently exhibited at the National Archaeological Museum of Rabat. Provenance determination of 28 samples was carried out by means of a multi-method approach combining mineralogical-petrographic data and C-O stable isotope analyses as the first step, and cathodoluminescence microscopy as a complementary technique to verify possible unusual alternative origins of some marbles. The analytical results obtained were compared with both the most reliable international databases and the few available studies dealing with the use of marble in other Roman towns in Morocco (e.g., Volubilis, Thamusida and Sala-Chellah). They point to a variety of classical marble sources such as Carrara, Mount Penteli, Paros, Marmara and probably Mount Filfila (Algeria), and prove a significant import of Iberian lithotypes.