Medieval glass beads (IMAGE) Université de Genève Caption The glass beads studied, unearthed by archaeological excavations in Dourou-Boro and Sadia, Mali, and Djoutoubaya, Senegal. Credit © UNIGE/Truffa Giachet/Spuhler Usage Restrictions © UNIGE/Truffa Giachet/Spuhler License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.