The accumulation of trapped electrons, and the gaps left behind in the spaces they vacated, occurs at a measurable rate proportional to the radiation received from a specimen’s immediate environment.
When a specimen is reheated, the trapped energy is released in the form of light (thermoluminescence) as the electrons escape.
After a period of cooling the energy storing process starts anew and a certain amount of stored energy is gained annually.
At the re-heating of a material sample taken from the fired object impulses of emitted light can be measured in the laboratory which correspond with the time interval between the present observation and the last firing.
At this point, the method seems to be a straightforward concept.
However, problems arise from assuming a uniform radiation dose rate over any significant period of time and assuming that the TMRD resulted from the object or artifact being in a strictly constrained environment identical to that in which it was found.
This is useful for ceramics, as it determines the date of firing, as well as for lava, or even sediments that were exposed to substantial sunlight.For example, a lithium fluoride crystal can preferentially respond to gamma thermal neutron, beta proton, or alpha particle radiation depending on whether it is constructed from The constancy of the RDR is even more problematic because it’s based on the uniformitarian assumption that the RDR has been constant.However, it’s well known among radiation physicists that RDRs vary with location, season, solar activity, and even time of day.Clay, which is used in the production of every day objects as well as objects of art, generally contains such minerals and radioactive isotopes.All radioactive energy accumulated and stored by the unfired clay in geological time is destroyed at the point of firing.