TL testing

TL testing is the best scientific test available to determine the "Zero" point or, date of manufacture of:

  • Terrcotta and low fired pottery

  • Porcelain and stoneware

  • Casting core bronzes

To determine the Zero point it is necessary to discover the last date of kiln firing.When a small sample is taken from an object and heated in the lab, a faint blue light is emitted. This Thermoluminescence, or TL for short, can be detected and measured using special light sensitive equipment. The measurements are used to calculate the date the object was either manufactured or last fired. The brighter the light, the older the object.TL testing is widely used by museums, dealers, collectors and auction houses as a means of verifying the dating of ancient artifacts.

Ollis and Oostermeijer Chinese Antiquities employs the services of "Oxford Authentication Ltd", a private company formed in 1997 by Doreen Stoneham, formerly with the Research Laboratory for Archaeology and History of Art at Oxford University, with over thirty years experience in TL testing. This company has representatives world-wide and is internationally recognised by major auction houses and institutions as a leader in TL testing.

For more information see also: Oxford Authentication Ltd

This information is given by kind permission of Oxford Authentication Ltd.

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