Photo: the “heads” of a contemporary coin, with a head of the god Bacchus, which was sampled as part of the project
A new scientific analysis of the composition of Roman money has brought new understanding to a financial crisis briefly mentioned by Roman statesman and writer Marcus Tullius Cicero in his essay on moral leadership, De Officiis, and resolved a debate long history.
Researchers from the University of Liverpool and the University of Warwick have analyzed coins from the era and found far greater debasement of coinage than historians thought, with coins that were in pure silver before 90 BC cut with up to 10% copper five years later.
Dr Matthew Ponting from the University of Liverpool, said: “The Romans were used to extremely fine silver coinage, so they may have lost faith in the denarius when it ceased to be pure. The precise level of debasement might have been less important to contemporaries than the mere realization that the coin was forged and no longer genuine “silver”.
Professor Butcher from the University of Warwick said: “The discovery of this significant fall in the value of the denarius has shed new light on Cicero’s allusions to a monetary crisis in 86 BC. Historians have long debated what the statesman and scholar meant when he wrote “money was thrown everywhere, so that no one could know what he had”. (De Officiis, 3:80) and we think we have now solved this puzzle.
The reference is part of an anecdote describing the selfish behavior of Marius Gratidianus, who took credit for a monetary reform proposal worked out jointly by the tribunes and the college of praetors and thus became extremely popular with the public.
But what was the cause of the “tossing” of the currency and what were the solutions for which Gratidianus took credit?
Rome and the Coins of the Mediterranean 200 BCE – 64 AD, a five-year ERC-funded research project aims to increase our understanding of the economies of classical Rome and other Mediterranean states by analyzing the composition of their pieces and by cross-referencing the discoveries with the historical file.
The research team includes Professor Kevin Butcher from the University of Warwick, Dr Matthew Ponting from the University of Liverpool and Dr Adrian Hillier from the ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory.
Dr Ponting added: ‘Our minimally invasive sampling technique used to take samples of these important coins revealed a significant drop in value of the denarius – from being a pure silver coin, the denarius initially fell to less than 95% fine, then it fell back to 90%, with some coins as low as 86%, suggesting a severe currency crisis.
Professor Kevin Butcher explains the background: “In the years after 91 BC. J.-C., the Roman State was in danger of going bankrupt. The Romans were at war with their own allies in Italy, and when the war ended in 89 BC. BC, there was a debt crisis.
“In 86 BC. J.-C., there also seems to have been a crisis of confidence in the currency. Cicero recounted how the Roman tribunes approached the college of praetors to resolve the crisis, before Gratidianus claimed sole credit for the collective effort.
“One theory is that Gratidianus fixed the exchange rate between the silver denarius and the bronze as (whose weight had only recently been reduced). Another is that he published a method for detecting false denarii , and thus restored confidence in the currency.
“Unfortunately, Cicero’s choice of words is too obscure for historians to determine exactly what was going on. His purpose in writing about it was not to illuminate monetary history; he was simply using the incident as an illustration of a Roman magistrate misbehaving by taking credit for the work of others.
“We thought for a long time that there had been a very slight devaluation of the denarius between 89-87; but was it enough to trigger a monetary crisis?
The results of the metallurgical analysis suggest that the financial difficulties encountered by Rome during these years led to a relaxation of standards at the mint in 90 BC, with the result that the silver content of the mint fell in two steps, so that by 87 BC the coinage was deliberately alloyed with 5-10% copper.
Professor Butcher added: ‘That might be the meaning of Cicero’s words: that the value of money was ‘tossed around’ because no one could be certain whether the denarii they possessed were pure or not.
“It is all the more remarkable that around the time Gratidianus issued his edict, the level of fineness rose sharply, reversing the debasement and restoring the denarius to a high quality coinage.
“Although the precise chronology remains uncertain, the new scientific data suggests that this may have been the main purpose of the Edict of Gratidianus, rather than something to do with the exchange rates between silver and bronze or the fake detection.”
In the decades that followed, the Romans avoided degrading the denarius again, until the state again faced huge expenses during the civil war between Pompey and Julius Caesar. Even then, Roman coinage did not go as far as it had during the time of Gratidianus.
These findings are part of a larger EU-funded study that aims to examine the financial and monetary strategies of Mediterranean states from c. 150 BCE to a major coinage reform in c. 64 CE by providing a detailed and reliable set of analyzes of the chemical composition of all major silver coins of this period.
“Rome and the Coins of the Mediterranean 200 BCE – 64 CE”, is a five-year project funded by the European Research Council and hosted by the Department of Classics and Ancient History at the University of Warwick. This is a collaboration between Professor Kevin Butcher of the University of Warwick, UK, Dr Matthew Ponting of the University of Liverpool, UK, and Dr Adrian Hillier of ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, UK. This project has received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme.