Glass was being made in Nigeria at least as far back as the 15th century, sometimes with a unique chemical composition, rather than being imported as previously claimed. The discovery is part of the reversal of the erasure of ancient African civilizations from history.
Slave traders and colonizers liked to portray the people they mistreated as lacking civilization. It made it much easier to justify atrocities to people back home, or even to themselves. So it is hardly surprising Europeans spent centuries discrediting the cultural and technological achievements of sub-Saharan Africans. Major accomplishments were either written out of the history books or improbably attributed to lost Europeans from other continents. If you think this process has stopped, look at the ongoing attempts to argue Africans have lower average intelligence than people from other continents, a claim that sits very uneasily with technological advances.
So when evidence emerged before World War I of extensive glasswork at Igbo Olokun, southwest Nigeria, centuries before, its significance was minimized. “The glass-encrusted containers and beads that have been uncovered there were viewed for many years as evidence that imported glass was remelted and reworked,” said Harvard University's Dr Abidemi Babatunde Babalola in a statement.
The claim was questioned 12 years ago when chemical analysis revealed a high-lime, high-alumina content (HLHA) that does not match that from other centers of glass production in Eurasia or Africa north of the Sahara. Now Babalola has confirmed in the Journal of Archaeological Science not only that Nigerians were making their glass from scratch, but that they were doing it long before Europeans began visiting nearby coastal areas.
Examining 52 beads from an astonishing haul of almost 13,000, Babalola, then at Rice University, found a mixture of HLHA beads consistent with the local geology, and some made from low-lime high-alumina (LLHA) glass. The two types of glass appear to have been made locally from granitic sand, including calcium carbonate, when required and were sometimes worked together to produce a composition carefully matched to its purpose. The beads come in a variety of colors reflecting the addition of one of MnO, Fe2O3, CuO, and CoO to make purple, blue-green, turquoise, and blue colors, respectively.
HLHA glass has been found widely across West Africa, indicating strong ancient trade networks throughout the region. Babalola concludes Igbo Olokun was a center for glassmaking from the 11th to 15th centuries.
Glass beads continue to have an important role in the Yoruba culture of the area today as part of necklaces, armlets, and beaded crowns.
Babalola's work also returned many glass-working materials, confirming Igbo Olokun as the center of glass manufacturing, rather than just distribution.