The property of some materials that have accumulated energy over a long period of becoming luminescent when pretreated and subjected to high temperatures, used as a means of dating ancient ceramics and other artifacts.
- ‘To determine the time since the object was last fired, a sample of around 30 mg is removed and heated to 500°C, which releases the stored energy in the form of light - this is thermoluminescence.’
- ‘The thermoluminescence does not manifest itself until a temperature of 932°F is reached.’
- ‘Many minerals heated at hundreds of degrees emit luminescence, so that thermoluminescence has been used initially in geology, archeological dating and radiation dosimetry.’
- ‘Scientists testing old occupation sites by thermoluminescence have suggested an Aboriginal presence of up to 60000 years.’
- ‘But with the advent of more sophisticated techniques, firstly with thermoluminescence and now with optically stimulated luminescence, our ability to define the limits of that chronology is much sharper.’
- ‘Perhaps one of the best-known techniques is thermoluminescence, which is used on ceramic works.’
We take a look at several popular, though confusing, punctuation marks.