M. Blet-Lemarquand
G. Sarah
B. Gratuze
J.-N. Barrandon
IRAMAT - Centre Ernest-Babelon, CNRS, Université d'Orléans, France

After the pioneering work of Meyers at the end of the 1960s, the Centre Ernest-Babelon developed and applied successfully two different nuclear methods using a cyclotron for numismatic studies: Proton Activation Analysis (PAA) and Fast Neutron Activation Analysis (FNAA). At the beginning of the 1970s PAA was developed to study ancient gold coinage. The judicious choice of the particle's energy (11 MeV) permits a non-destructive multielement analysis of these objects. In the 1980s FNAA was improved to determine non-destructively the contents of the major, minor and trace elements in silver and copper alloys coins. These two nuclear methods were successfully used to study numismatic and historical issues covering all periods and geographical areas. But from one hand the radioactivity entails many constrains and from the other hand these nuclear methods appeared to be not sensible enough or even not able to measure some elements that could be interesting for provenance studies.

Therefore a complementary method was recently and successfully developed for the non-destructive analysis of archaeological gold and silver artefacts: Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS). A comparison between these methods will be done for each of the coined metals and alloys. Their advantages and drawbacks will be illustrated with numismatic examples.