However, there were no other historical records to support that a Roman emperor named Sponsian ever existed, according to a press release. And, at the time, “Sponsian” was not a name known to have existed in ancient Rome.
Their workmanship and style, including confusing inscriptions, differed from the general style of genuine Roman coins from the mid-3rd century, according to the study. As a result, they were dismissed as ill-conceived forgeries.
The coin’s authenticity has been debated since its discovery in 1713. Credit: University of Glasgow
Now researchers from University College London (UCL) and the University of Glasgow in the UK claim to have discovered features indicating authenticity.
They used powerful microscopes in visible and ultraviolet light, as well as scanning electron microscopy and spectroscopy – studying how light at different wavelengths is absorbed or reflected – to examine the pieces.
In total, they analyzed four coins from the treasure found in 1713, one of which depicts Sponsian. All four are on display in The Hunterian at the University of Glasgow.
A wear pattern has been identified on the Sponsian coin, suggesting that it was in active circulation. The researchers also found soil deposits, which means it was probably buried in the ground for a long time before being dug up and exposed to the air.
“Scientific analysis of these ultra-rare coins rescues Emperor Sponsian from obscurity,” said the study’s lead author, Paul N. Pearson, associate research professor in the Department of Earth Sciences at UCL, in the press release.
“Our evidence suggests he ruled Roman Dacia, an isolated gold-mining outpost, at a time when the empire was plagued by civil wars and the borderlands were overrun by raiding invaders,” he added.
Head of Dacia
The province of Dacia, which was cut off from the rest of the Roman Empire around AD 260, was a region prized for its gold mines and mineral resources, according to UCL.
Sponsian never controlled an official mint or ruled Rome, the researchers said, but may have become a local commander-in-chief who took charge during a time of chaos and civil war to protect the people of Dacia.
The Sponsian series of coins were used to pay senior soldiers and officials, who kept them as a store of wealth, the researchers proposed.
Powerful visible and ultraviolet light microscopes, as well as scanning electron microscopy and spectroscopy, were used to assess the coin’s authenticity. Credit: The Hunterian / University of Glasgow
From the results, it “would appear that Sponsian should be rehabilitated as a historical figure,” the study concluded.
The researchers added that while “nothing can be known about him with certainty”, the coins analyzed “provide clues as to his possible place in history”.
“Unscientific and baseless”
Not everyone is convinced, however.
Despite the study’s findings, some experts, including in the field of numismatics – the study or collection of money – still believe the coin is fake.
“Like everyone in the world of numismatics, I firmly believe that this coin is a modern forgery,” Jérôme Mairat, curator of the Heberden Coin Room at the Ashmolean Museum in Oxford, England, told CNN.
“This whole theory – that the piece is genuine – is both unscientific and baseless,” he added.
The coin was used to pay senior soldiers and officials in the isolated Roman province of Dacia, the researchers suggest. Credit: University of Glasgow
Pearson, however, insisted that the researchers had reached “a clear conclusion” on the coins’ authenticity, telling CNN in an email: “For the great history of Rome, Sponsian is little more than than a historical footnote – but a footnote that should nevertheless be reinstated!”
He said the researchers wanted to start a conversation with Roman historians and archaeologists to try to test their Sponsian hypothesis.
“To understand the last days of Roman power in the province of Dacia, and the history of Romania, it is potentially more important, but our results have just been published and the academic debate has only just begun.”