gems, archaeology, archaeogemology, Africa, Libya

The part of Africa to be studied lies between the Middle Niger basin and the central valley of the Nile. It stretches from Sansanding in the west to Khartoum in the east, running across modern Mali, Niger, Chad, and Sudan, including the northern parts of Burkina Faso and Nigeria. Today, it is a region of little rainfall. Stretching down to the Sudan savannah in the south, its northern area is predominantly the Sahel and the desert. There are indications, however, that early in the first millennium of our era, it received more rainfall, and such locations as Kumbi, the metropolis of the ancient kingdom of Ghana, Timbuktu, and the Chad basin lay well within the Sudan savannah. As far north as Tibesti, the vegetation was luxuriant enough for camel herding and possibly for raising other large animals, such as donkeys, horses, and cattle. And so, the present Saharan part up to the latitude of Tibesti, Ténéré, and Aïr would have been of the Sahelian type. The discussion below will deal with that open region at a time when it was covered by grass and shrubs which made contact easier than it is today.