Problems encountered in a TL and ESR study of natural monohydrocalcite

A natural monohydrocalcite sample from Australia was submitted to gamma -ir radiations and analysed by TL and ESR. Spurious TL signals are observed, pr obably due to the presence of water and organic impurities. TL and ESR dose response curves are presented and discussed. The organic impurities seem r esponsible for a delay of around 200 Gy in the increase of the TL peaks and the appearance of the ESR carbonate derived radicals (supralinear behaviou r). Dating was not possible and no direct correlation exists between the th ree TL peaks and the ESR signals due to CO3-, CO2- and SO2- radicals. (C) 2 000 Elsevier Science Ltd. All rights reserved.