A leaflet from Daybreak describing the TL technique in more detail and giving a bibliography will be provided to interested persons.
The phenomenon of thermoluminescence was first described by the English chemist Robert Boyle in 1663.
This radiation may in some cases contribute over half the total dose.
Unfortunately, it is not possible to achieve this precision for the majority of art objects.
Among the reasons for this is the small amount of material that may be taken for testing.
It is an absolute dating method, and does not depend on comparison with similar objects (as does obsidian hydration dating, for example).
The thermoluminescence technique is the only physical means of determining the absolute age of pottery presently available.
The typical turn-round time for providing a date is circa 3-4 months, although, rapid dating (circa 4-6 weeks or sometimes less, depending on machine time and sample type) using our fast track service can be undertaken.
OSL dating results including Dose equivalent (De) estimate, dose rate measurement and calculated age will be reported as a short pdf document by email.
By comparing this light output with that produced by known doses of radiation, the amount of radiation absorbed by the material may be found.
Most mineral materials, including the constituents of pottery, have the property of thermoluminescence (TL), where part of the energy from radioactive decay in and around the mineral is stored (in the form of trapped electrons) and later released as light upon strong heating (as the electrons are detrapped and combine with lattice ions).
It was employed in the 1950's as a method for radiation dose measurement, and soon was proposed for archaeological dating.
By the mid-1960's, its validity as an absolute dating technique was established by workers at Oxford and Birmingham in England, Riso in Denmark, and at the University of Pennsylvania in the U. The Research Laboratory for Archaeology at Oxford, in particular, has played a major role in TL research.
The age range for pottery and other ceramics covers the entire period in which these materials have been produced.