reality dating game - Obsidian hydration dating

It was employed in the 1950's as a method for radiation dose measurement, and soon was proposed for archaeological dating.

obsidian hydration dating-71

While not so accurate as radiocarbon dating, which cannot date pottery (except from soot deposits on cooking pots), TL has found considerable usefulness in the authenticity of ceramic art objects where high precision is not necessary.

Since the university laboratories involved with TL are research facilities, they generally will not accept art objects for authentication on a routine basis.

Using this information often reduces the uncertainty to 15-25 per cent. Nearly any mineral material which has been heated above 500C at a time one wishes to know is a candidate for TL dating. Porcelains, being nearly vitrified, are a special case requiring a fairly large solid core sample, and TL dating of intact objects is not recommended because of the damage caused by sampling.

Most porcelain dating is done for insurance purposes on broken objects.

These will give an authentic date for a bogus object.

It must be realized that TL dating is but one of the criteria for judging authenticity.

Some clays are hardly thermoluminescent at all; some may not have a straight-line relationship between dose and TL; spurious luminescence due to chemical or pressure effects may mask the radiation-induced TL; occasionally, a condition called "anomalous fading", where part of the TL is unstable, may lessen the accuracy of the dose measurement.

Generally speaking, when a sample is drilled and there is no information available about the burial environment, one may expect up to 40 per cent uncertainty.

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.

Much stoneware is not so hard as porcelain and may be sampled by drilling.

Tags: , ,