Optical dating of quartz and feldspars: A comparative study from Wonderkrater, a Middle Stone Age site of South Africa

While quartz is the most used dosimeter, it has been shown that feldspars provide many advantages over quartz, essentially in terms of reproducibility and sensitivity. Unfortunately, they also suffer from instability in their luminescence signal, known as anomalous fading, which leads to an underestimation in age if no correction is applied in a spring and peat mound archaeological context, we explore the possibility of obtaining a single age for both quartz and feldspar fractions from the same sample. This work first highlights the importance of selecting two dosimeters in an archaeological or geological context. It also put in the foreground the time-consuming but gratifying approach of comparing large and small aliquots. Finally, we present feldspars with a barely detectable and measurable fading rate, whatever the protocol applied, suggesting that the solution to anomalous fading might be to find feldspar grains that do not fade.

► We obtain luminescence ages from an archaeological site at a spring and peat mound. ► We highlight the importance of selecting two dosimeters in an archaeological context. ► We highlight the approach of comparing large and small aliquots. ► The solution to anomalous fading is to find feldspar grains that do not fade.