A new historical perspective regarding the baptismal font of the cathedral of Monreale (Sicily): the identification of a reused Roman labrum by an analytical approach

The Cathedral of Monreale (not far from the city of Palermo) is one of the most famous monuments of the Arab-Norman period in Sicily recently added to the World Heritage list by UNESCO. It is well known above all for its structure and the magnificence mosaic decorations inside. In the church it is also conserved a Baptismal Font made of coloured limestone and dated back to the first decade of the 17th century. The present study deals with this valuable object with the aim of obtaining information about the nature and provenance of the coloured limestone constituting the basin. Laboratory analyses were thus carried out on representative stone samples by means of polarized light microscopy as well as C and O stable isotope mass spectrometry. The obtained results revealed the provenance of the coloured marble from the island of Chios (Aegean Sea), accordingly corroborating the suggestive hypothesis of the re-employment of a marble basin (labrum) of Roman age during the Renaissance. This paper provides a new contribution to the understanding of the historical and architectural development of the Cathedral of Monreale highlighting a new example of re-employment and reworking of precious stone in antiquity.