Islamic glass in the Christian Kingdom of Alwa: Chemistry of shards from Soba,Nubia, Sudan

Excavations at Soba, the capital of Alwa, between 2019 and 2022 yielded more than 30 glass fragments in addition to a glass cosmetic bottle. An analysis of 30 glass samples has identified glass belonging to a number of compositional groups. The majority of fragments were made of plant ash-soda glass produced in the Middle East (Iran, Iraq) between the 9th and 10th centuries, and in the Eastern Mediterranean (Levant and Egypt) between the mid-10th and mid-12th centuries. Seven fragments were made of mineral–soda-lime glass produced in 9th-century Egypt and three high-lead glasses find analogies in the 9th- to 11th-century glass. Archeological evidence, as well as textual sources, leave no doubt about Alwa’s intense transcultural connections. This article provides the first insight into the chemistry of glass shards from medieval Nubia, and the results of analysis contribute to evidence for long-distance contacts of Soba, the capital of one of the medieval kingdoms of Sahelian Africa.