A 400-year-old gold coin worth thousands of pounds has been found among a pile of old tender at the back of a dressing table drawer.

The highly valuable Charles I gold Unite (20 shillings) coin, dating back to around 1625, was discovered hidden among around 200 old coins and banknotes in Tunbridge Wells.

It is now set to go under the hammer at Hansons Auctioneers for an estimate of £1,500-£2,500 – despite its owner originally thinking it was fake after finding it.

The man who struck gold was Robin Fletcher, an antiques valuer and manager of Hansons Royal Tunbridge Wells’ office in The Pantiles Arcade.

He was invited to a property in the town to assess a collection of modern Royal Mint proof coins which had belonged to a client’s late aunt.

He said: “The vendor found the coin at the back of a dressing table drawer when she was sorting through her late aunt’s effects. Both the vendor and her husband assumed it must be fake so took little notice of it and tossed it into a box of mixed 20th-century coins.

“As always, I carefully sifted through the coins to see if there was anything of value and was shocked when I saw a glint of gold. As I was told it was a fake I didn’t do a close inspection until I got it back to the office. I then realised I’d struck gold. I phoned the seller to let her know. She was surprised and delighted to hear the valuation.

“It was amazing to pluck out a 400-year-old Charles I gold coin from a mish-mash of mainly low-value coins. Charles I (1600-1649) was King of England, Scotland, and Ireland from March 27, 1625 until his execution in 1649. We will never know how this historical gem ended up languishing in a dressing table drawer for, probably for decades.”

Robin explained that gold items sometimes gets overlooked when it’s discovered by chance as people automatically assume they can’t be lucky enough to have found the real thing.

He continued: “The find seems timely ahead of the coronation of King Charles III on May 6. I am thrilled for the owner.

“Many people have piles of old coins stuck in drawers or tins at home, perhaps inherited and added to by various relatives over many decades. As well as plenty of pre-decimal British coins we see lots of holiday money gathered from all over the world.

“Often coins have little value but, along the way, perhaps an ancestor in the family picked up a rarity or two that could be worth more than their weight in gold. Coin collecting was, and still is, popular. The problem with coins is that they’re so small they can get forgotten. They end up hidden away at the back of drawers, lost under sofa cushions or even left in pockets.

“I’d advise anyone with old coins sitting around at home to go through them carefully and call in the experts to double-check their value.”

The Charles I coin will be offered in Hansons Royal Tunbridge Wells inaugural auction on May 23.

Further entries are invited. To discuss a potential consignment or book a valuation, call Robin Fletcher on 01892 573540 or email rfletcher@hansonsauctioneers.co.uk.