Rare silver coin of Roman Emperor Carausius set to fetch up to £8,000 at auction

Detectorist Mike Clark, 73, found it at an organised dig in a field in June.

A rare silver coin of the Roman Emperor Carausius, who made Britain an independent state, is set to fetch up to £8,000 at auction.

Detectorist Mike Clark, 73, found the denarius at an organised dig in a field in June.

After drawing a blank in the morning, the retired fisherman found a pound coin before getting a signal at a depth of six inches in South Brewham, Somerset.

He said: "I recognised it immediately as a denarius of the Emperor Carausius."

Carausius usurped power in AD286 and made Britain an independent state.

The coin, which was never published, features a laureate bust of the usurper.

Carausius commanded the Roman fleet 'Classis Britannica', which was based in the English Channel.

In AD 286 the emperor Maximian ordered his execution after Carausius was suspected of concealing treasure captured from pirates.

Carausius then declared himself Emperor of Britain and northern Gaul making Britain an independent state.

For this he is sometimes regarded as the first 'brexiteer'.

The coin features a radiate Lion holding a thunderbolt.

The letters RSR appear before the Lion which are the abbreviation for 'Rodeunt Saturnia Regna' from the poet Virgil's 'Eclogues' meaning the kingdom of Saturn returns.

Mike, of Wimborne, Dorset, will share proceeds with the landowner.

But, it turns out he's not the only one who's been coining it in with his metal detector.

A group of seven treasure hunters were left thrilled after discovering 2,584 silver coins - which ended up being bought for a whopping £4.3 million.

The collection, purchased by South West Heritage Trust, is made up of King Harold II pennies from the end of Anglo-Saxon England and William the Conqueror coins, after the 1066 Norman conquest.

The bulk of the haul was found by Adam Staples and Lisa Grace, who are believed to have become millionaires through the sale.

They had been training five friends on how to use metal detectors when they made the discovery.

The landowner, whose identity is not being revealed, is entitled to 50 per cent of the proceeds.

The haul, found in the Chew Valley of Somerset, is the highest value treasure on record, beating the famous Staffordshire Hoard from 2009, which was worth £3.3m.