This radiation may come from radioactive substances such as uranium, present in the clay or burial medium, or from cosmic radiation.
When the ceramic is heated to a very high temperature (over 932°F [500°C]), these electrons fall back to the ground state, emitting light in the process and resetting the "clock" to zero.
Scientists can determine how many years have passed since a ceramic was fired by heating it in the laboratory and measuring how much light is given off.
Thermoluminescence dating has the advantage of covering the time interval between radiocarbon and potassium-argon dating, or 40,000–200,000 years.
In addition, it can be used to date materials that cannot be dated with these other two methods.
The study of physical qualities of quartz extracted from sediments shows that the TL peak at 330 deg C (the peak used for TL dating) has second-order kinetics. 463-471; Risoe National Laboratory; Roskilde (Denmark); 3.
The existence of two emission centres, whose intensity is determined by the prehistory of the quartz provides information on the character of dose response. specialist seminar on TL and ESR dating; Elsinore (Denmark); 26-; Available from: V.