Roman coins once believed to be fake reveal long-lost historical figure: ScienceAlert

Long dismissed as counterfeits, handful of ancient Roman coins discovered in Transylvania more than three centuries ago were authenticated by re-analysis.

It is not difficult to see why the coins – dated to 260 CE could have been considered fake. Where most ancient coins display the head of an emperor, one of the artifacts displays a mysterious figure not depicted in any other known document.

On some is affixed the name “Sponsian”, a figure of Roman authority that history seems to have forgotten.

“Scientific analysis of these ultra-rare coins rescues Emperor Sponsian from obscurity,” says Paul Pearson, earth scientist at University College London, who led the study.

Discovered in 1713, the aurei gold coins had been declared fake in the middle of the 19th century by the leading expert of the time, a man named Henry Cohen, due to numerous irregularities. They differ in workmanship and style from genuine pieces of their time, for example, vary greatly in weight, have mixed designs, and messed up markings.

Imitation Roman coins were made outside the empire at the time, and again during the Renaissance period as clearly fake trinkets. Later, more realistic counterfeits were produced with simulated wear intended to fool wealthy coin collectors.

The gold weight of the 1713 collection exceeds US$20,000 in modern value. Three of the four pieces held at the Hunterian Museum in Scotland over the past two centuries depict actual emperors, including one known as Philip the Arab, but the fourth depicts the mysterious man.

The name Sponsian is also very particular, the only other known example of it coming from a Roman funerary inscription “Nicodemus Sponsian” dated to the first century. Moreover, this only other instance of the name was not even known at the time the coins were discovered.

“We emphasize here that the inscription was excavated in the 1720s and therefore could not have been known to a hypothetical forger, who therefore would have had to invent a particular name which later proved to be authentic”, explains the team in its article.

Using ultraviolet imaging, visible light and scanning electron microscopy, Pearson and his colleagues discovered wear scratches covering the surfaces of the parts. This suggests that the tokens had been subject to heavy use and circulation among other coins, and had not been deliberately scratched to mimic use. Tiny bits of soil cemented to the surfaces support the claim that the artifacts were really buried for a long time.

Wear marks on the coins suggest use as real currency. (Pearson, et al., PLOS A2022)

The coins have various compositions, all over 90% gold but also with different small mixtures of silver and copper. This differs from two genuine Roman coins used for comparison purposes, which are essentially pure gold.

The Sponsian coin, in particular, has a distinct mix of gold, silver, and copper that is different from the ratios measured in other coins. While this may suggest the coins are modern forgeries, Pearson and his colleagues conclude that it likely means the coins were minted outside of ancient Rome, “most likely made from imperfectly refined ore”.

Mineral deposits on Roman coins up close
Soil deposits on a real aureus and one of the “fake” coins. (Pearson, et al., PLOS A2022)

Historians have previously speculated that Sponsian may have been a brief usurper during the reign of Philip the Arab in the 240s. But the fact that Philip appears on some of the coins in the same collection contradicts the idea that Sponsian l spoofed, say the researchers.

“These observations force a reassessment of Sponsian as a historical figure,” write Pearson and his team. “We suggest he was most likely an army commander in the isolated Roman province of Dacia during the military crisis of the 260s CE.”

So, while he may not have ruled the entirety of Rome, Sponsian appears to have fashioned his own little empire in a remote gold-mining outpost, with crudely minted coinage using metals from local mines, likely after the Roman Empire began to become fractured, researchers suspect.

“We suggest that Dacia cut itself off from the imperial center around 260 [CE] and effectively seceded under his own military regime, which first invented precious metal bullion using old Republican-era designs, then using the names of more recent previous emperors who had achieved a certain success in the region, and finally under the name of a local commander-in-chief”, explains the team.

Sponsian’s “roughly made coins” supported a functioning monetary economy that persisted locally for an appreciable period.

This would explain why Sponsian never appeared in official Roman records, as well as the strangeness of the coins.

“Our evidence suggests [Sponsian] ruled Roman Dacia… at a time when the empire was plagued by civil wars and the borderlands were overrun by plundering invaders,” Pearson concludes.

This research was published in PLOS ONE.

Leave a Reply

Your email address will not be published. Required fields are marked *