
However, there are no other historical records to support that a Roman emperor named Sponsianus ever existed, according to a press release. And at that time “Sponsian” was not a name known to have existed in ancient Rome.
Their workmanship and style, including puzzling inscriptions, differed from the general style of authentic mid-3rd-century Roman coins, according to the study. As a result, they were dismissed as poorly made forgeries.

The coin’s authenticity has been debated since it was discovered in 1713. credit: University of Glasgow
Now researchers from University College London (UCL) and the University of Glasgow in the United Kingdom say they have discovered characteristics indicative of authenticity.
They used powerful microscopes in visible and ultraviolet light, plus scanning electron microscopy and spectroscopy – studying how light of different wavelengths is absorbed or reflected – to examine the coins.
In total, they analyzed four coins from the hoard discovered in 1713, one of which is with Sponsian. All four are on display at The Hunterian at the University of Glasgow.
A wear pattern was identified on the Sponsian coin, suggesting that it was in active circulation. The researchers also found earth deposits, meaning it was likely buried in the soil for a long time before being dug up and exposed to the air.
“Scientific analysis of these ultra-rare coins rescues Emperor Sponsianus from obscurity,” lead study author Paul N. Pearson, a research associate professor in UCL’s Department of Earth Sciences, said in the press release.
“Our evidence suggests that he ruled Roman Dacia, an isolated gold-mining outpost, at a time when the empire was engulfed in civil wars and the frontier areas were overrun by marauding invaders,” he added.
Leader of Dacia
The province of Dacia, which was cut off from the rest of the Roman Empire around 260 AD, was a region valued for its gold mines and mineral resources, according to UCL.
Sponsianus never controlled an official mint or ruled Rome, the researchers said, but likely became a local commander-in-chief who took over during a period of chaos and civil war to protect Dacia’s population.
The sponson coins were used to pay senior soldiers and officials who kept them as a store of wealth, the researchers suggest.

Powerful microscopes in visible and ultraviolet light, plus scanning electron microscopy and spectroscopy, were used to assess the coin’s authenticity. credit: Hunterian/University of Glasgow
From the findings, “it appears that Sponsian should be rehabilitated as a historical figure,” the study concluded.
The researchers add that while “nothing can be known for sure about him”, the coins analyzed “give clues to his possible place in history”.
“Unscientific and unreasonable”
However, not everyone is convinced.
Despite the study’s findings, some experts, including in the field of numismatics — the study or collection of currency — still believe the coin is a fake.
“Like everyone in the numismatic world, I strongly believe that this coin is a modern forgery,” Jerome Mairat, curator of the Heberdon Coin Room at the Ashmolean Museum in Oxford, England, told CNN.
“This whole theory – that the coin is genuine – is both unscientific and baseless,” he added.

The coin was used to pay senior soldiers and officials in the breakaway Roman province of Dacia, researchers suggest. credit: University of Glasgow
Pearson, however, insisted that researchers have reached a “clear conclusion” about the coins’ authenticity, telling CNN in an email: “To the great story of Rome, the Sponsian is little more than a historical footnote — but a footnote that must nonetheless be restored!”
He said the researchers want to start a conversation with Roman historians and archaeologists to try to test their Sponsian hypothesis.
“For understanding the dying days of Roman rule 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 is just beginning.”