First Remarks about the Pavement of the Newly Discovered Mithraeum of the Colored Marbles at Ostia and New Investigations on Roman and Late Roman White and Colored Marbles from Insula IV, ix

This paper focuses on the latest research about the marble fragments found during the archaeological investigations carried out since 2007 by the Department of History and Cultures of the University of Bologna, within the Ostia Marina Project, here presented as a continuation, deepening and updating of the contribution made at Asmosia Conference X (2010). Investigations continued fruitfully over the years and led to a further expansion of the excavated area, with the addition to the thermal complex named the “Silenus Baths” (sector A), of new structures from sector B, among which the significant discovery of a new mithraeum stands out, referred to as being “of the colored marbles”. The spelaeum of this mithraeum still preserves the nearly intact pavement made with many different types of reused marble. Technical and archaeological investigations of the pavement are here presented, as well as the results of the quantitative and qualitative analysis of the marbles