This are two bifacial foliates from the Nubian desert (brown chert; max 12 cm long), found in the 1930ies, which show strong similarities to the Lupemban and early Nubian MSA of East Africa. The Sangoan and Lupemban of Central Africa and the Eastern Lowlands are MSA- technocomplexes dated roughly between 400-150 k.a BP. They can be identified on the basis of “heavy duty” core axes and picks (Sangoan) and smaller and parallel sided core axes and bifacial lanceolates, often combined with a blade element and Levallois flake tools (Lupemban). At Twin Rivers and Kalambo Falls there is the first African indication for backed tool technology, suggestive for hafting these artifacts. JD Clark suggested these heavy duty tools were good for wood-working, based on association of Kalambo Falls site in Zambia with deciduous woodland, and preserved wood at site. However, a number of other sites, such as those excavated by McBrearty in Kenya and at Sai 8-B-11 were clearly occupied by open grassland or savannas.
The Sangoan is thought to be older than Lupemban, but the stratigraphic relationship is not well documented except for the great Site of Kalambo Falls in Zambia where the Sangoan is stratified beneath the Lupemban and at the site of Sai 8-B-11 in northern Sudan.
At Sai 8-B-11 the two lowermost strata can be attributed to the Sangoan because of the presence of core-axes and distinctive flake reduction strategies. Given the evidence of systematic blade production and the presence of a lanceolate in addition to small and regular core-axes, the upper assemblage of this sequence is qualified as Lupemban. It is suggested, that this ensemble marks the beginning of the MSA in the Nil valley, which is later evolving towards the “Nubian -MSA”, during OIS6/5. During this MSA foliates with a technology and typology that resemble the pieces shown here, appeared.