The radiation causes charge to remain within the grains in structurally unstable "electron traps".
The trapped charge accumulates over time at a rate determined by the amount of background radiation at the location where the sample was buried.
Better still, unlike radiocarbon dating, the effect luminescence dating measures increases with time.
Luminescence dating refers to a group of methods of determining how long ago mineral grains were last exposed to sunlight or sufficient heating.It is useful to geologists and archaeologists who want to know when such an event occurred.The error limits on the dates obtained are typically in the range of 5 to 10%.Our standard cost for OSL dating is £550 VAT per sample but prices can vary depending on the nature and number of samples (see our schedule of charges).Fieldwork (within Southern England) including in-situ radioactivity measurements, sample collection and travel to and from site can be undertaken at a daily rate of £300 VAT.
We are also able to conduct sample collection outside of the UK if the client is willing to cover additional transport, accommodation and subsistence costs.
It uses various methods to stimulate and measure luminescence It includes techniques such as optically stimulated luminescence (OSL), infrared stimulated luminescence (IRSL), and thermoluminescence (TL).
"Optical dating" typically refers to OSL and IRSL, but not TL.
TL dating is a matter of comparing the energy stored in a crystal to what "ought" to be there, thereby coming up with a date-of-last-heated.
In the same way, more or less, OSL (optically stimulated luminescence) dating measures the last time an object was exposed to sunlight.
Luminescence dating is particularly appropriate when radiocarbon dating is not possible (either where no suitable material is available or for ages beyond the radiocarbon age limit) or for applications affected by radiocarbon plateau effects (e.g.