Jane Bassett
Abstract
Thermoluminescence (TL) dating is one of many tools used for the authentication and technical study of works of art within the Department of Decorative Arts and Sculpture at the J. Paul Getty Museum. This paper considers the lessons learned through attempts to use the TL technique to date seventy-one European objects attributed to the Renaissance through the 18th century, including: glazed and unglazed terracotta sculpture, faience, majolica, and glazed earthenware, as well as clay-based and plaster-based bronze casting cores. When considering whether or not TL dating should be attempted for a work of art, issues such as material type, object history, sample size, and error limits should be taken into consideration. Examples of European materials that are difficult to date using the technique are given. Recommendations are made for safely taking and handling samples, and for choosing a TL lab. The results have been categorized and illustrate that in certain circumstances, TL dating has proven to be a pivotal aspect of our authenticity studies. Optically Stimulated Luminescence (OSL), a related technique that shows promise for greater precision, is briefly described. In summary, we have found that when approached with deliberation and caution, thermoluminescence dating can be a very useful addition to a broad-based sculpture study.