The diadem worn here, cylindrical in form with overlapping leaves, either laurel or olive, most likely represents a gold original. Such diadems signified that the wearer held a priestly office. For a similar diadem on a portrait of a priest see the example at The Ashmolean Museum, Oxford [no. AN2005.11], pp. 5-6 in Smith and Vickers, "A Roman priest from the eastern Mediterranean," The Ashmolean, 49.