M. Járó - L. Költő szerk.: Archaeometrical research in Hungary (Budapest, 1988)

Analysis - BIRÓ Tamás: Nuclear methods in archaeometry developed in the Institute of Isotopes

coin No. 17 coin No. 18 cu\ \ \ 1 • Au \ i f Pb Fig. 3 XRF spectra of coins found in a counterfeiter mint Thermocurrent dating iiii) Thermoluminescence dating carried out in our Institute is discussed in another article in this volume [5]. The phenomenon analogous to TL, i.e. thermostimulated current or conductivity (TSC or briefly TC), has received much less attention in archaeometry. Dating and provenience studies can be carried out similarly to TL based on the analogous mechanism. Hwang and Frernlin reported TC measurements on basalt samples obtaining dates in agreement with K—

Ar dates [6]. We investigated the feasibility of this method on obsidian from the Tokaj area, Hungary. The preliminary results were a bit surprising: in spite of the intense TL peak at about 300 °C, no TC peak was observed in this region, but at higher temperatures (700-900 °C) unusually high-current (mA) peaks could be detected [7]. These are probably due to polarization effects or to ionic conductivity (Fig. 4). However, the reproducibility was poor, TC or rather TSPC might be used for the characterization of obsidian. Further measurements are planned to clarify the interpretation of the results and also to reproduce measurements on basalt.