Optically stimulated luminescence dating at rose cottage cave
Blades from the Howiesons Poort assemblages were produced by soft hammer percussion on marginal platforms and the backed tools of this industry subsequently fashioned from these flakes.
Sarah Wurz's study shows that the general assemblage, frequency of retouch pieces, and the variability in formal tool morphologies still need to be looked into further.
OSL ages were compared to a well defined radiocarbon chronology from RCC, and any inconsistencies would motivate closer sorting of the different dating techniques.
The mode of sediment deposition via different depositional mechanisms such as, fluvial, and clast spalling present difficult challenges in assessing the zero age value of a sample.
The ability of the SAR protocol to pick out feldspar contamination was therefore not conclusive, and single grain measurements had to be used to differentiate quartz and feldspar grains.
The likelihood of age contamination from problematic depositional events was not supported and the results suggest that aeolian deposition was the main mechanism at the site.
For the time being this cultural phenomenon is unique, isolated, stratigraphically and chronologically intercalated between two Middle Stone Age industries lacking bone tools.
One may hypothesize that the makers of this culture did not survive to a later age and thus their innovative venture had no relationship to the appearance of similar bone and antler tools, beads and pendants in Eurasia.
Accordingly, we cannot identify any particular climatic attribute that is consistently and uniquely associated with any MSA industry the Stillbay coincided (within error) with the Toba volcanic super-eruption and with the end of megadroughts in tropical Africa, whereas the Howiesons Poort is not associated with any such known events.