Islamic Archaeology in the Comoros: The Swahili and the Rock Crystal Trade with the Abbasid and Fatimid Caliphates

Dembeni was one of the largest and richest archaeological sites in East Africa during the early Islamic period. At its height, between the 9th and the 12th centuries, there was a period of intense trading activity, initially with the Abbasids in the Persian Gulf, and then with the Fatimid Caliphate in the Red Sea. Dembeni has yielded archaeological finds indicating an unprecedented degree of wealth for the time, including a large amount of early Chinese and Persian ceramics, as well as glassware from all over the Islamic world. This accumulation of goods did not happen by chance, and since the first excavations at Dembeni archaeologists have sought the origin of the site’s wealth. Recent excavations at Dembeni suggest that the prosperity of the site was linked to the lucrative rock crystal trade, which accounts for the ubiquity of imported goods. Of Malagasy origin, the rock crystal was exported to Mayotte, where Muslim tradesmen exchanged ceramics, fabric, beads, and glass for the precious rock crystal, with only the highest-quality pieces being exported to Baghdad and Cairo. Evidence points to Dembeni as a major distribution centre for the Malagasy rock crystal in the Indian Ocean.