Amateur Archaeologist Stumbles Onto Trove of Coins Dated to Constantine the Great’s Reign

Found in Switzerland, some of the buried Roman coins were minted during a time of relative political stability, between 332 and 335 C.E.

Coins in a clay pot
The clay pot contained 1,290 Roman coins. Archäologie Baselland

It’s not every day that a jaunt with a metal detector turns up something truly revelatory. One might expect to find a vintage engagement ring or a necklace lost to time—but a set of over a thousand Roman coins? That seems unlikely.

Yet that’s exactly what happened to Daniel Lüdin as he perused a section of forest in Bubendorf, Switzerland, close to Wildenstein Castle, on an early September day in 2021. As the amateur archaeologist swept his metal detector across the ground, a “strong signal” suddenly emitted from the machine, according to a statement from Archäologie Baselland, the archaeology department for the state of Basel-Landschaft, or Baselland. When Lüdin began to dig, he was shocked by what he found: a clay pot filled with 1,290 coins.

In accordance with proper archaeological protocol, Lüdin reburied the pot and contacted local experts, who dated the cache of coins to the fourth century C.E., during the reign of Roman emperor Constantine the Great (306 to 337 C.E.). At the time, Switzerland was part of the Roman Empire.

Based on the coins’ composition—copper alloy and traces of silver—the treasure wouldn’t have gone far at the time of its burial. Instead, it was simply a large stack of “small change,” equal to about two months of earnings for a soldier, per the statement. Collectively, the coins amounted to as much as a single gold solidus, “a pure gold coin introduced by Emperor Constantine during the late Roman Empire that weighed about 0.15 ounces,” writes Live Science’s Laura Geggel.

Roman coins found in Switzerland
The coins were all minted during the reign of Constantine the Great (306 to 337 C.E.). They feature portraits of the emperor and his relatives on the front. Rahel C. Ackermann Inventory of Swiss Coin Finds

Finding hidden coins from the late Roman period, which scholars define as roughly 250 to 450 C.E., is not unusual. Earlier this year, a badger in northwest Spain made headlines after digging up a hoard of more than 90 ancient coins, as Jack Guy reported for CNN in January. What’s different about the newly unearthed coins in Switzerland is their specific timeframe. The most recent specimens date to between 332 and 335 C.E.—a period of relative prosperity from which few Roman coin hoards survive.

“In troubled times, triggered by civil wars, incursions by neighboring ethnic groups or economic crises, many people buried their valuables in the ground to protect them from unauthorized access,” notes the statement, per Google Translate. “During the time when the pot from Bubendorf was hidden, there are hardly any comparable hoards in the entire Roman Empire. These years are characterized more by their political stability and some economic recovery.”

The timing of the coins makes the find “very important,” Reto Marti, head archaeologist at Archäologie Baselland, tells Live Science. “It will give a very detailed insight into the use of money and the circulation of coins in the time of ... Constantine the Great.”

Academics generally agree that people bury coin hoards during times of great stress: for example, during the Black Death or the English Reformation. But discoveries in recent decades have led some scholars to speculate that certain caches also served as ritual offerings, “perhaps [ensuring] the wealth of a farming community ... as insurance for a good harvest or good weather,” noted Current Archaeology in 2010.

The newly discovered coins were found on the border of three Roman estates, indicating they may have been buried as a border sanctuary or a sacrifice to the gods, according to the statement.

While surveying the coins with a CT scan, the archaeologists spotted a piece of cowhide dividing the cache in two, indicating the money may have belonged to two different people or groups. For those who want to take a closer look at the find, researchers have created a 3-D model of the coins in situ.

“A stroke of luck is certainly also the survival of the storage vessel, which contained not only coins but also a piece of leather, organic material that rarely survives,” Marjanko Pilekić, a numismatist who was not involved in the analysis, tells Live Science.

Further research could reveal “which coins belonged to which side [of each Roman estate], which may help in the interpretation,” Pilekić adds.

In recent years, archaeologists, amateurs and even farmers have spotted Roman coins in Switzerland. In 2015, more than 4,000 bronze and silver coins from around the end of the third century C.E. were found in a molehill. A few years later, 293 silver coins spanning the reigns of emperors Nero through Commodus were spotted in a forest.

Modern-day Switzerland became part of the Roman Empire in 15 B.C.E., under the emperor Augustus. By the midway point of Constantine’s reign, Rome’s boundaries encompassed much of Western and Southern Europe, as well as parts of the Middle East and Africa.

Constantine was perhaps best known for issuing the Edict of Milan, which allowed Christians to worship freely. The emperor himself converted to Christianity on his deathbed.

Constantine also renamed Byzantium (modern-day Istanbul) Constantinople and refashioned the city as a “second Rome.” That change perhaps signaled some of the instability and fear that may have prompted coin hoarding.

According to Encyclopedia Britannica, “Rome had long been unsuited to the strategic needs of the empire. It was now to be left in splendid isolation, as an enormously wealthy and prestigious city—still the emotional focus of the empire—but of limited political importance.”

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