Continued survey of the superficial deposits in the Northern Sperrgebiet, Namibia, prompts revision of previous interpretations of their ages. Fossiliferous gray calcified sandstone intercalated with travertine at Hexen Kessel was originally estimated to correlate to the Pliocene 50 metre marine package, but the 2018 field survey resulted in the discovery of stone tools in situ in the sand indicating the likelihood that the deposits are younger than previously envisaged. Correlation to the 30 metre marine package (Pleistocene) is possible, but some of the sandstone may represent aeolian deposits younger than this marine package. The gray sands likely represent aeolian deposits which accumulated on the flanks of the Hexen Kessel Valley where freshwater seeping to the surface cemented them with calcium carbonate. The locality has obvious archaeological interest: early hominids foraging for marine food resources, transport of raw material for manufacturing stone tools and knapping activities all focussed around freshwater springs in a hyper-arid environment. Keywords: Pliocene, Pleistocene, Stone tools, Patella, Phragmites, Namibia.