Thermally and optically stimulated luminescence dating of later prehistoric pottery

Thermoluminescence dates have been determined for groups of pottery sherds from recent excavations at Fordham, Cambridgeshire and Willington Hill Farm, Derbyshire. Although, the average precision in the individual date determinations is 10.5 +/- 4.3 %, the precision in dating single contents or groups of features can be improved by calculating weighted mean dates for appropriate groups of pottery sherds. Such weighted mean dates can then be used in deducing site chronologies, as illustrated here using the dates for the Fordham. and the Willington. Hill Farm pottery. Additionally, through the approach of dating multiple sherds from each context, a high degree of residuality in the pottery from one context at Fordham was identified. The dominant source of error in the thermoluminescence dates is the scatter in the data used in determining the palaeodose. The use of optically stimulated luminescence was investigated and the preliminary results discussed here indicate that this error is significantly reduced when optical rather than thermal stimulation is used. Thus, optical stimulation techniques could lead to the determination of luminescence dates of sufficiently high precision to be useful to date individual sherds.