A groundbreaking study published in the Journal of Archaeological Science has identified a major trade link connecting the early Iron Age cultures of the Niger Delta with the Western Mediterranean. By tracing the isotopic signature of cassiterite (tin ore) found in Phoenician bronze artifacts in Iberia, researchers discovered that a significant portion of the metal originated from the Jos Plateau in modern-day Nigeria. In exchange, thousands of Mediterranean cowrie shells have been excavated in contemporaneous West African sites.
This "Cassiterite and Cowrie" network suggests that trans-Saharan trade was far more active and ancient than previously believed, predating the camel caravans of the medieval period. The research indicates that a series of relay stations across the Sahel and the Sahara allowed for the movement of heavy metals and luxury goods, effectively integrating West Africa into the Bronze and Iron Age global economy of the Mediterranean world.