Composition and origins of decorated glass from Umayyad Cordoba (Spain).

Recent archaeological excavations carried out in the western suburbs of Cordoba (Spain) brought to light numerous fragments of archaeological glass from the caliphal period (929-1031 CE). The typological and compositional analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) of 66 fragments enabled the identification of different types of base glass and glass working techniques, identifying local productions, imports and decorative imitations of eastern models. The studied fragments include Mesopotamian, Levantine, Egyptian and possibly Sicilian soda-rich plant ash glass categories, and various glass-decorating techniques such as mould-blowing, pressing, cutting, staining or gilding. The systematic comparison of the trace element patterns of several relief-cut objects identified both imported ware and a locally manufactured sample, whereas all mould-blown pieces were made from locally sourced raw materials. Iberian glassworkers seem to have preferred mould-blowing, probably because of the distinct working properties of locally available high lead glass. The results thus confirm the continuous long-distance exchange of vitreous material, as well as the existence of multiple glassmaking centres in the Iberian Peninsula, illustrating a link between secondary glass working techniques and chemical composition. Furthermore, the identification of several fragments belonging to the same object based on chemical composition allowed us to reconstruct entire vessels and thereby expand the repertoire of known typologies circulating in Umayyad Spain. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s40494-021-00505-4.