Technological changes in the glazed wares of northern Tunisia in the transition from Fatimid to Zirid rule

A representative selection of glazed ceramics recovered from medieval Islamic contexts excavated in the former Roman port of Utica (North Tunisia) has revealed new data about medieval glaze technologies in the central Mediterranean. Stratified sequences of pottery have established four main phases of occupation which span the mid-10th to the mid-11th centuries. The Utica assemblage demonstrates significant changes in the range of glazed wares in the Zirid period with respect to the late Fatimid period: whereas polychrome yellow-amber glazed ware, produced in the Kairouan region, was practically the only glazed ware supplied to Utica in the Fatimid period, an increasingly varied range of polychrome glazed wares was produced in various techniques in the late 10th century, early Zirid period. These new glazed ware types become dominant in the early 11th century. Up to six different glazing techniques have been identified, including transparent and opaque glazes with underglaze and overglaze decoration respectively. The absence of tin in all the glazed vessels sampled from Utica confirms the data obtained in a previous study from Bir Ftouha. Though it has been repeatedly stated that tin was used to produce the white background of Fatimid-Zirid glazed wares in Tunisia, this was achieved by adding quartz to the glaze. Some imports of glazed ceramics from Sicily and al-Andalus have been detected: their appearance in the early-mid 11th century is significant as seems to indicate a first stage in the re-activation of Mediterranean commerce, which increased in the course of the following centuries.