A tiny ceramic jug buried nearly 600 years ago in Russia held more than 2,600 silver coins. Archaeologists have a chilling theory about why its wealthy owner never returned

A small ceramic jug discovered near the historic Kremlin in Kolomna, Russia, has turned out to be an extraordinary medieval treasure. Hidden inside were more than 2,600 silver coins, many of them rare and previously unknown to researchers.

The discovery is being described as the largest intact coin hoard from the first half of the 15th century found in Russia, offering archaeologists an unusually detailed look at money, wealth and trade in medieval Kolomna.

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A small jug was hiding a huge medieval fortune

Archaeologists from the Institute of Archaeology of the Russian Academy of Sciences discovered the ceramic jug during rescue excavations in the historic centre of Kolomna, around 114 kilometres southeast of Moscow.

The jug had been placed in a shallow pit near the city's historic Kremlin. It was described as a small, elegant, slip-painted ceramic vessel — an unassuming container that had remained underground for roughly six centuries.

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Inside, however, were more than 2,600 silver dengi, a common medieval Russian coin denomination. Researchers say the hoard provides an almost frozen-in-time picture of the money circulating in Kolomna during the early 15th century.

More than 350 coin varieties were previously unknown

The coins are especially valuable to historians because the hoard was found intact rather than as a scattered collection.

Most were minted under Grand Princes Vasily I Dmitrievich and Vasily II Vasilyevich, rulers of the Grand Principality of Moscow. Kolomna was an important city during this period and ranked just behind Moscow in importance within the principality.

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Among the most striking examples are rare coins showing a bird in flight. Even more surprising, researchers have identified more than 350 previously unknown varieties among the coins.

Because medieval coins were struck using individually cut dies, tiny differences in lettering and imagery can help specialists determine when and where particular coins were produced.

The unusually large collection could therefore help researchers reconstruct coin production in Kolomna over a period of at least 15 years.

The owner may have been extremely wealthy

The contents also reveal something about the person who buried them. Archaeologists believe the owner was probably a wealthy and high-status individual. Possibilities include a senior official connected to the Grand Prince or a highly successful merchant.

Popular Mechanics reported that the silver would have represented enough wealth to potentially buy two homes in town and a herd of horses at the time. That makes the disappearance of the owner even more puzzling.

Did a medieval plague claim the owner?

The coins provide an important clue. The newest coins in the jug date to the second half of the 1420s. That suggests the hoard was buried around that period. At roughly the same time, epidemic outbreaks were sweeping through the Russian principalities between 1424 and 1427.

Researchers therefore suggest that the owner may have died during the epidemic and never had the opportunity to retrieve the hidden fortune. However, archaeologists have not established that the owner was definitely a plague victim. The timing simply makes the possibility plausible.