A collection of battered 17th century trading tokens thought to have been lost during the chaos of The Great Fire of London could fetch up to £20,000 at auction.

Roger Green, who is originally from Kent, spent 35 years collecting the tokens along the muddy banks of the River Thames.

Many of the monetary artefacts were only recently discovered and a quarter of the 370 tokens up for sale display the year 1666, the year of the devastating blaze.

Experts believe the tiny tokens, which were once used as currency as no small-value coins were being minted, flew from the pockets of traders fleeing the capital.

The entire single-owner collection is expected to fetch between £15,000 and £20,000 at Hansons Auctioneers later this month.

Several were dug up by lifelong collector Mr Green, who is now selling the Kent tokens which he first took an interest in as someone who hails from the county.

“I started collecting coins but gradually moved to tokens," he said. "I find them more interesting as they’re personal to the people who issued and used them."

Mr Green, a lifelong collector of everything from stamps to beer mats, joined the Society of Thames Mudlarks and Antiquarians in 1985.

He inherited his passion for collecting from his grandma, who bought him an album and packet of foreign stamps when he was eight.

"River digging opened a whole new area and over the years I managed to find quite a few tokens, mostly from London and Southwark but also from other areas of the country," he said.

Among the finds up for sale is a token representing Marie Allen from the medieval village of Wye, near Canterbury.

But one of his most prized finds is from Erith, near Dartford, only a mile or so from where Mr Green used to live.

He added: "It was found at Billingsgate in London and was my reward for a particularly arduous dig. Tokens from the river are usually in good condition as they’re in a sealed layer of silt which preserves them from the ravages of time.

“Now I’ve decided it’s time to let my collection go. I’m getting older and have fewer opportunities to add new pieces. Also, as I now live in Dorset, the draw of Kent pieces is not so strong."

The Great Fire of London raged on for four days in September 1666.

Blazes wreaked havoc on the medieval city of London as fires engulfed 13,200 houses, 87 parish churches and ravaged St Paul’s Cathedral.

In total, it is estimated 70,000 of the city’s 80,000 inhabitants lost their homes.

Alan Smith, head of Hansons’ Historica department, believes finding so many tokens from 1666 around the banks of the River Thames is no coincidence.

“During the panic and chaos of The Great Fire of London, the Thames offered water to quell the flames and a means of escape by boat," he said.

"We hear about Bitcoin and a cashless society but finding new ways to trade and pay for items is nothing new."

"In the panic, it’s likely many of these tiny trading tokens flew out of pockets and bags. At the time, tokens were used as currency in London as no small-value coins were being minted by the government.

“To enable them to do business, traders pressed their own farthing or half-penny tokens to give as change. They could be spent locally and were widely used between 1648 and 1673.”

Mr Smith added: “This token collection is impressive. We hear about Bitcoin and a cashless society but finding new ways to trade and pay for items is nothing new. Hundreds of years ago, people came up with innovative ways to do just that.”

Now Mr Green hopes the sale of his collection will inspire others to take up the dig.

"I found these fascinating and learned much about the world," he said. "For me, the 17th century is a particularly fascinating period as it was the time of the English Civil War and then the Commonwealth before a return to the monarchy.

"I hope the sale of my tokens will inspire others to enjoy collecting them."

The Roger Green Tokens Collection will be sold in Hansons Auctioneers’ between May 21 and 22 at Historica Auction at Hansons, Heage Lane, Etwall, Derbyshire, DE65 6LS.

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