Resources and the Roman Imperial economy: The metallurgy of the denarius as a source of information on the exploitation of natural resources and the political and economic context
Final Report Abstract
Since coins are generally an officially produced material, provenance studies of the metal used to produce them can provide important information on the logistical, infrastructural and organizational capacities of central authorities. Thus, it is not surprising that ancient coins have been the subject of a large number of archaeometallurgical studies, in particular involving lead isotopes. The composition of the silver in the coin metal of Roman Imperial denarii has been intensively investigated in recent years by Kevin Butcher and Matthew Ponting (The Metallurgy of Roman Silver Coinage. Cambridge 2014). However, their work concentrated primarily on the chemical composition, with only a relatively smaller number of isotopic analyses being carried out, and concentrating on specific questions. To complement the investigations of Butcher and Ponting, more than 200 additional coins from the period 30 BC to AD 240 were sampled for isotopic analysis. Besides standard lead isotopes, these analyses also included copper and silver isotopes, which were performed in Bochum, at the Frankfurt Isotope and Element Research Center FIERCE, the Laboratoire de Géologie de Lyon, École normale supérieure de Lyon, and in the Institute for Geosciences at the Goethe University Frankfurt. The combination of isotopic analyses of different elements has provided deeper, sometimes surprising insights, qualifying the information previousy provided by lead isotopes alone. In particular, the combination of elemental and multi-isotope analysis proved ideal for evaluating key moments in the development of the denarius coinage of the Roman Imperial period and changes in the raw materials used. Thus, Nero’s coinage reform, the effects of Trajan’s wars, and changes in metal sources late in Hadrian’s reign are mirrored in the composition of the denarii. That key events in the development of the denarius coinage are visible in such clear changes in the material, was not expected. It will be interesting to see what further insights the dissertation can provide beyond the results reported here. In any case, it is already apparent that, in spite of the increasing resistance to (micro-)invasive sampling methods, it is absolutely necessary to obtain samples of material that consist of metal that is as uncorroded as possible and unaffected by intentional surface treatment such as enrichment, since only in this way can meaningful results be obtained.
Publications
-
Metallanalysen römisch-kaiserzeitlicher Denare. In: Chr. Herm, St. Merkel, M. Schreiner, R. Wiesinger (eds.), Archäometrie und Denkmalpflege 2019, Metalla Sonderheft 9, 2019, 212-213.
Greifelt, T., Klein, S. & Wigg-Wolf, D.
-
Geochemical and isotopic characterisation of the coin metal of Roman denarii - a multifactorial application tool for numismatic, political, strategic and logistic contexts in the Republic and the Imperial Era. In: Greiff, S., Schlütter, F., Kronz, A., and Klein, S., Archäometrie und Denkmalpflege Metalla Sonderheft 11, 2021, 26-27.
Greifelt, T., Klein, S. & Wigg-Wolf, D.
-
Geochemical and isotopic characterisation of the coin metal of Roman denarii - A multifactorial application tool for numismatic, political, strategic and logistic contexts in the Republic and the Imperial Era.. Goldschmidt2021 abstracts. European Association of Geochemistry.
Greifelt, Tim; Klein, Sabine & Wigg-Wolf, David
