Obsidian as a natural product derived from volcanic activity, was highly desired by ancient populations for its cutting ability as well as its black/red color. Volcanoes associated with the rifting of the Red Sea produced lava fields both in Arabia and Africa. Many of these also produced obsidian. Trace element analysis, using X-Ray Diffraction or Multispectral banding, provides the signature for each obsidian source. Archaeological specimens can then be traced to their specific source. Neolithic and Bronze Age populations of Arabia and Africa traded extensively for this commodity from sources in Yemen (Dhamar-Reda) and Ethiopia/Eritrea. The vast percentage of Ancient Egyptian obsidian (Nagada II-III/O.K.) came from these southern Red Sea sources. A smaller amount of Neolithic Levantine obsidians may have also come from this area. Ubaid period (ca. 4500 B.C.) obsidians from Qatar have also been traced to Yemen sources.