Western Connections of Northeast Africa: The Garnet Evidence from Late Antique Nubia, Sudan

Abstract

Outstanding garnet beads were found recently in an elite tumulus dated to the fourth century AD and located at the cemetery of Hagar el-Beida in the Upper Nubian Nile Valley region. Whereas contacts of Northeast Africa with South Asia have just been proven through analysis of glass beads found in Nubia and dating to the time of intensive Indian Ocean trade, scientific evidence for Nubia's link with the regions to the west was lacking. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to determine the elemental composition of three garnet beads to gain information about their type and origin. Additionally, we analyzed twelve garnets from two nearby alluvial placer deposits. While the garnet beads are inclusion-free Cr-poor and Ti-rich pyropes related to alkaline mafic volcanic rocks, the local garnet deposits are shown to be inclusion-rich almandines and thus unrelated to the investigated Nubian beads. Detailed comparison of data from Merovingian cloisonné jewellery and all known sources of the Cr-poor and Ti-rich pyropes shows identical ranges of elemental contents. The source of raw materials for the beads found in Nubia has been not identified with certainty yet, but sources in Portugal and Nigeria are suggested and a connection is shown to similar garnets from Merovingian contexts.