Exploring complexity in luminescence dating of quartz and feldspars at the Middle Stone Age site of Mwulu's cave (Limpopo, South Africa)

Luminescence dating is applied to sediments from Mwulu's Cave, whose lithics have been typologically considered Middle Stone Age (MSA) and have been previously assigned to what is called the Pietersburg industry. This industry is, however, poorly defined both chronologically and typologically. Luminescence methods were applied to both quartz and potassium feldspars by two different laboratories. Age results from single-grain quartz are much younger than those from multi-grain aliquots and this is attributed to the use of different fits to the growth curves and the effect of this on samples near saturation. Single-grain potassium feldspar ages are much older than the single-grain quartz ages. Application of various methods to address anomalous fading produced broadly consistent results among samples. Most K-feldspar samples appear to be about 90 ka. These are compared to other South African MSA sequences and industries.