The silver deniers which were the currency of Merovingian Gaul from c. 670 until Pepin's reform in the mid-eighth century have been studied with devoted thoroughness by Lafaurie. He has been at pains to make it clear that our understanding of the series is restricted by the extreme incompleteness and patchiness of the evidence. The available coins, which nearly all come from a handful of hoards, evidently represent only a tiny proportion of the dies originally used at more than fifty mints. The survival rate seems to be distinctly lower than in the contemporary Anglo-Saxon series.

One aspect of the Merovingian silver coinage which has not yet been explored is its alloy. These few pages, dedicated with deep respect and gratitude to Philip Grierson, who supervised my first steps in numismatic research at Cambridge twenty years ago, provide some information to fill the lacuna. Professor Grierson generously made his own collection available for chemical analysis, and the results from a selection of one hundred specimens are presented below (Table 11). Since few numismatists, probably, will realise how scarce Merovingian silver coins are – far more so than Merovingian gold – I may add that the Ashmolean Museum has only two comparable pieces.

Professor Hall kindly allowed the use of the ‘Isoprobe’, an X-ray fluorescence focusing spectrometer in the Research Laboratory for Archaeology and the History of Art, at Oxford. Limitations of space preclude a detailed account of the instrument, the sample preparation, or the standards used for calibration.