Armlets, 9th/10th century, excavated at Igbo Richard, Igbo Ukwu, eastern Nigeria. Beads and copper wire, height 14.9 cm. National Commission for Museums and Monuments, Abuja, Nigeria, IR.416 and IR.417. Photograph by Uche James Iroha

Glass beads mass-produced in Albania, Egypt, and Venice were in high demand across Africa’s Western Sudan and forest regions during the medieval period. It had been assumed that glass was manufactured on only a limited scale in West Africa; however, new archaeological research shows extensive glass making and glass bead production beginning in at least the 11th century at Igbo Olokun, in the city of Ife (Nigeria). Blue glass beads are the most abundant, but brown, green, yellow, clear, striped, and dichroic beads, which display different colors under certain lighting conditions, were also produced. Beads from Igbo Olokun have been excavated at Gao (Mali), proof that they circulated widely.