It's easy to be tricked into thinking there's a kind of old-world magic tied to ancient buried treasure.

One afternoon in January, a couple of weeks into the third national lockdown, reporter, Chris Hunter was burying a brick as a makeshift foundation for a woodshed in the garden, when a strange coincidence occurred.

"Look out for any archaeology," his assistant had said, as he was about to start digging, and just at that moment a man walked along the path next to the garden carrying a metal detector - like he'd been summoned from thin air by the very mention of "archaeology".

It was probably nothing more than a coincidence, but the weird moment of synchronicity led to an intriguing tale of lost treasure.

Chris put off the digging for a moment. "Found anything?" He called over to him, and he stopped.

"Well not much today," said the man, who turned out to be one David Callow, a 41-year-old air conditioning installer and part time detectorist from Tonbridge.

But he had found something recently. In fact he was still buzzing with excitement over a find from a couple of months previously; and he produced his phone to show pictures of two gold coins he'd dug up from a field a few miles north of his home town.

They turned out to be rare gold tremissis from the Merovingian dynasty - the ruling family of the Franks from the middle of the 5th century until 751 - and only 115 such coins have been recorded in Britain before.

How these specific tremissis turned up in the UK will never be known exactly but they originate from a time of social turmoil across Europe, in the wake of the collapse of the Roman Empire.

It's a time of strife and internal struggle in many countries, with no doubt intermittent periods of lawlessness; and a time in Britain when no coins were being minted by the tribes left free of Roman rule.

You can let your mind wander in a thousand possible journeys as you follow those coins through that tattered European landscape, on their way to their final destination in a field near Tonbridge.

Except it's not quite their final destination - because their fate, and potentially their value, will now be decided by the British Museum.

For David, it's all part of a journey that began at the end of what had seemed a luckless session of metal detecting last year. His friend Guy had already gone back to the car while David and his son Lawrence headed to another section of the field for one last half-hour.

"He was ready to go and he said 'you carry on, I'll sit in the car'," recalled David. "He was reading the newspaper and wanted to get back for dinner. So I did a bit more."

Shortly after that his metal detector made a noise he hadn't heard it make before - and his curiosity built to excitement as he dug and pulled out something shining from the ground.

"I knew it was gold that I'd dug up but I didn't know exactly what it was because I didn't have any spray," he added. "You don't rub these things, so I took it back to where they were and said I think we've found something.

"Lawrence said 'what is it?' and Guy said in a pirate's voice 'that be gold...'

After that all three walked back over to the site where the gold had been found. David recalled how Lawrence was directly behind him, while Guy was 15 paces ahead....

"And then it was the same sound as before," he said. "I'd never heard this sound. You get so many distinctive sounds for certain metals, so I said to Lawrence I think I could have another one here. I dug the hole and another clod and Lawrence saw it for himself. He said 'oh god it's another one'."

David's clearly got the golden touch, because on another site nearby a short while later he found another gold coin - a Gallo-Belgic gold stater. Not quite as rare as the tremissis, it's nevertheless older, from around 150BC - and has its origins in another time of turmoil.

"That coin has got a story behind it," added David. "They was minted to pay mercenaries fighting in the Gaul war against Julius Caesar. It could have been bought over by a mercenary from the continent. They were only struck on one side - most coins were struck on both sides, but the theory was they were produced hastily to get the mercenaries to fight."

If there's a secret behind David's in-built radar for ancient gold, he doesn't know what it is.

"Most people that have been doing it for 40 years never find gold coins," he says. "I've been doing it 10-12 years and it's in 2020 that I've dug my first gold coins.

My friend's another metal detectorist - he says I've jumped the gun. You get halfpennies and things like that but I've found a 2000 year-old-one and two 1500-year-old ones. It's just luck, or my machine is working very well. It's a weird one."

"I never expect to find gold or anything of great value. It's just the satisfaction. It's the 'what could it be?' It's the mystery. Even if it's an old button. My boy dug up a military button from New Zealand and so that's come a long way. You think how did it end up here?

"It's all the fun of the hobby and the researching of what you find.

"Every piece of junk I pull out of the ground I take it away and bung it up the shed."

With son Lawrence, eight, and Anna, 12, both keen on the hobby, the family are already expanding their chances of striking gold once more.

But for now he's still excited about the possibilities surrounding the two tremissis. Once the British Museum have reached a conclusion it could then be up to a coroner to decide if the find is technically "treasure".

He added: "To be honest I have no idea on what they might fetch at auction. If you were to get two serious collectors fighting over them. But what I do know is that they are both extremely rare and one of them is a new variety which I believe means it’s the only one of its kind know to exist."

Meanwhile Kent County Council archaeology expert Jo Ahmet has written a report for the British Museum on the finds, but would not be drawn into hazarding a guess at their value.

A former field archaeologist who was led to his current role having found himself "far too attracted by shiny things" he knows well the strange draw of buried gold - and he also knows it doesn't necessarily go hand in hand with well-conducted archaeology.

Hence his reticence to talk in precise terms about such things as find locations and value. But he admits they're exciting, and explained some of the historical context behind the coins.

"You've got to remember tremissis are rare across Europe," he said, "but if you're going to find something in Britain you're more likely to find it in Kent because Kent is one of the wealthiest areas in the time period.

"We've recorded 115 of this type of tremissis across the country. Some of them were turned into jewellery but even then it's around 120. If you compare that to Roman coins, we've got 300,000.

"In that period Kent has amazing connections to Europe during the early medieval period and what people used to call the Dark Ages.

A lot of this high value material tends to be found around North Kent and East Kent because of the maritime links. David's find are not in a part of Kent you would expect - it's unusual."
Jo suggested the coins could have been simply lost at one point or were perhaps be part of a "deposition" - purposely buried as a horde - which he feels is less likely.

"It's difficult to tell without the context," he adds. "If something's in a pot or a ditch you know the context, but these are from the plough zone so they've been mixed up and disturbed."

As for the Gallo-Belgic stater, while it might be the most common kind of gold coin in Europe, he noted the horse design has special significance in Kent, as a form of it would become the symbol of the county.

So while the secrets of such coins might never be revealed, they remain a fascinating - maybe even magical - a point of contact between us and our ancestors.

If you think you've uncovered treasure - gold or silver over 300 years old, or prehistoric metalwork - email flo@kent.gov.uk

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