Analysis of the Notches of Ancient Serrated Denars

A number of serrated silver denars of the Roman Republic and a Greek bronze coin were investigated, paying special attention to the notches, in order to reveal their production technique. Particular interest was devoted to three contemporary forgeries of serrated denars, because the official pure silver issues were also available for inspection. Several microbeam analytical techniques were applied, such as scanning electron microscopy (SEM), electron probe micro-analysis (EPMA) and secondary ion mass spectrometry (SIMS). The surfaces of the notches, which show traces of the tools used, were investigated by SEM. In the case of the forged coins, the thickness of the silver layer (inside the notches as well as on the surface of the coin) was determined by SEM and SIMS. The main components of the surfaces were similar in both cases as measured by EPMA. Combining the results, it is possible to reconstruct the steps in the production of the serrated denars. The investigations also permit a review of different opinions about the purpose of the notches