A Roman coin found by a metal detectorist 30 years ago has been revealed to be 2,000 years old and worth £10,000.
Tom Thomas, 62, kept the coin as part of an amateur collection until he was persuaded by a friend to take it to experts for valuation two years ago.
There, the metal detectorist found that the small gold timepiece was a Carausius Denarius Roman coin and the only one like it in the world.
Mr Thomas 'thought nothing of it' when he found the coin, which dates back to AD 286-93, in a field in Berkshire because he had found many others like it.
On the day, he said he had to dig down really deep compared to other coins, about eight inches, to reach it.
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The coin, which was dug up in a farmer's field in Berkshire and dates back to AD 286-93 and is now set to go up for sale at an auctioneers in Derbyshire with a guide price of £10,000. The coin features the Roman goddess Salus feeding a snake rising from an altar
But when friend and fellow metal detectorist Mark Becher spotted it at a family barbecue, he told Tom to get it looked at.
The retired policeman from Reading, Berkshire, said: 'I knew it to be a Roman coin as I had found others in the past. I put it with my small collection and thought nothing more of it.
'I've been metal detecting for more than 30 years and I've found lots of different coins and other Roman artefacts.
'It turned out to be the only one of its kind in the world.
He said that if he hadn't thrown a family barbecue for Mr Becher to spot it, he may never have known.
'Mark contacted other experts, including the British Museum, and no-one had seen anything else like it before.'
The coin, which was dug up in a farmer's field in Berkshire and dates back to AD 286-93, is now set to go up for sale at Hansons Auctioneers, in Derbyshire with a guide price of £10,000.
The coin, which is registered with the Portable Antiquities Scheme (PAS), features the Roman goddess Salus feeding a snake rising from an altar.
A Roman coin found by a metal detectorist 30 years ago has been revealed to be 2,000 years old and worth £10,000. Tom Thomas, 62, kept the coin as part of an amateur collection until he was persuaded by a friend to take it to experts for valuation
Tom Thomas 'thought nothing of it' when he found the coin in a field In Berkshire because he had found many others like it. On the day, he said he had to dig down really deep compared to other coins, about eight inches, to reach it
Mr Thomas added: 'I remember the day I found it.
