Detection of anomalous fading in archaeological ceramics

Abstract

Experiments were carried out to monitor the anomalous fading IR stimulated luminescence (IRSL) and thermoluminescence (TL) signals from fine-grained pottery samples. The TL signals were found to give a good linear fit when plotted against the logarithm of storage time, with little data scatter. The IRSL method of making repeated brief measurements on a few aliquots gave a much larger scatter and, thus, a less precisely defined fading rate. Use of the latter method will lead to the misidentification of some weakly fading samples as non-fading. No acceleration of the fading rate was observed by increasing the storage temperature from 10 to 50°C.