The thermoluminescent sensitivity to radiation of quartz samples separated from ancient pottery and from beach sand was investigated as a function of previous irradiation and previous firing to various temperatures. Irradiation with up to 38 kilorad of alpha particles or 400 rad of x-radiation produces no observed change in the sensitivity. It is known from previous work that the sensitivity to alpha particles is much less than that to x-radiation. The sensitivity to both types of radiation increases markedly after firing to temperatures above 867°C. These observations may indicate a source of error when dating earlier pottery samples by thermoluminescence. -- AATA