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Articles

• Liritzis, Ioannis
• Vafiadou, Asimina

An updated abridgement of the novel thermoluminescence (TL) technique that datesmonuments made by large stone blocks, as well as stone objects, is made. During the process ofstone block preparation (cutting and carving, or sculpturing) and prior its construction, the solarradiation (UV and optical spectrum) bleaches the optically sensitive electron traps in the carvedsurface down to a variable depth. During exposure for a time interval the sunlight sets the lightsensitiveTL clock to zero. If the stone is made of granite, basalt, sandstone rock types, the sunexposedinterval in minutes is enough to erase luminescencent traps. However, for calcitic stonesthis period varies between several hours to dozen of hours. In the latter case a technique is devisedto estimate the bleaching time in antiquity, and thus the residual value, which serves as the 'zerotime' upon which luminescence builds up until today.The total archaeological equivalent dose or total luminescence acquired by the minerals in theparticular stone is measured by Optical Stimulated Luminescence (OSL) techniques, while forcalcitic stones only thermoluminescence is at present applied with involved errors of the order of7-15% (Liritzis 2001). A new quartz / feldspar technique for limestone monuments is presentedenabling their dating by established single aliquot / single gain OSL methodology.Application examples from Greece covering the period 3rd millennium to classical time, and thepotential to dating world megalithics is explored.

• History and Archaeology

• Αρχαιολογία

Thermoluminescence, Optical luminescence, Dating, Bleaching, Megalithics, Granite, Limestone