Archaeometric investigations of sgraffito ceramic tiles (Fifteenth-sixteenth centuries) recovered from excavations in Udine (North-east Italy)

Most of the Renaissance sgraffito tiles excavated in Udine (Italy) constitu te a homogeneous group, the tile body having a CaO/MgO molar ratio = 3:2. T hey were produced using a dolomite- and calcite-containing clay fired at 90 0950%C. A small group of samples, with a lower firing temperature and a CaO /MgO ratio = 2:3, was probably produced in a different factory. Slip and tr ansparent glaze, characterized by optical microscopy and inductively couple d plasma atomic emission spectrometry, are an illite-rich clay and a lead s ilicate, respectively.