A slightly rounded flagstone at Vindolanda turned out to be something much rarer.

Archaeologist Andrew Birley was excavating a fourth-century barrack at the Roman fort in northern England last month when he noticed a stone positioned on its edge among many others. “I gave it a bit of a pull, and this beautiful little carving came out perfectly preserved,” he tells the Telegraph’s Dalya Alberge. “What a lovely moment.”

After consulting other scholars, Birley realised he had found a rare depiction of a Roman genius, a protective spirit or deity believed to bring good fortune and prosperity to a person, household or place.

Once he knew what it was, the discovery “somehow felt entirely appropriate,” Birley says in a statement from the Vindolanda Trust, the charity that manages the fort. “It was almost as though Vindolanda itself had reached out to the team and quietly said, ‘We approve of what you are doing.’”

The Romans viewed genii, the plural form of the word, as “a sort of guardian angel, a higher self,” according to Encyclopaedia Britannica.

Archaeologists think the specimen was deliberately buried beneath a barrack floor at Vindolanda, which operated as a northern frontier outpost between roughly 85 C.E. and the ninth century. The fort sits near Hadrian’s Wall, the 117-kilometre stone fortification that once marked the northwest boundary of the Roman Empire.

The figurine is the first of its kind found at Vindolanda, where excavations have been underway since the 1830s. Birley discovered it on June 16, and archaeologists have since been conserving the sculpture for public display at the fort’s museum.

References to genii are relatively common in ancient literature, suggesting worship of these symbolic guardians was widespread among Romans living in Britain. But archaeologists rarely find the objects themselves.

“There are not many from Roman Britain,” Birley tells the Telegraph. “But each one is lovely because a genius represents a spirit of place.”

The sandstone sculpture measures about 43 centimetres tall and 23 centimetres wide, and the stone is a little more than 8 centimetres thick. In one hand, the figure holds a cornucopia, a horn of plenty overflowing with food that symbolises abundance and prosperity. In the other, it holds a patera, a shallow dish used in ritual offerings.

Archaeologists think the 1,600-year-old relief was once part of a larger domestic shrine before being reused as construction material. They suspect a local artist made it, either a mason at Vindolanda or a nearby sculptor.

That also “gives it more of a sense of place,” Birley tells the Telegraph. “That’s really what we’re looking for as archaeologists, that connection with the real people who lived there.”

Other examples have turned up in Roman Britain before. In 1933, archaeologists excavating the niche of a building in the settlement outside Housesteads, another Roman fort near Hadrian’s Wall, found a relief carving dating to between 225 and 250 C.E. It depicts three hooded gods in thick cloaks and is known as genii cuculatti, or “hooded spirits.”

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