Thermoluminescence is a process in which certain materials emit light when they are heated. This phenomenon occurs in minerals, such as quartz and feldspar, which trap electrons when exposed to radiation over time. When these materials are heated, the trapped electrons are released, producing light as they return to their original state. This technique is often used in archaeology and geology for dating artifacts and geological samples. By measuring the amount of light emitted, scientists can determine when the material was last heated, providing valuable information about its history and age.