Rare Coins: 'Leopard' coin from 1344 to go on sale

A very old and very rare coin from the Middle Ages is due to go on sale soon.

The rare 'leopard' florin coin dates from January 1344 and was minted in 23-carat gold at the Tower of London.

It had a value at the time of three shillings or 36 silver pennies and was in circulation for only seven months before it was withdrawn.

It was found by a retired engineer in a field in Norfolk and is expected to sell for over £100,000!

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The rare gold "leopard" coin dates back to the reign of Edward III.

It's known as a leopard coin because it features an illustration of a leopard sitting upright and wearing a banner.

Over time, leopards in heraldry became what we'd now often consider to be lions in badges like the England football team's Three Lions.

The first florins in England were made during Edward's rule. Florin is a word for a coin that was borrowed from other European money - the original Florins were from Florence in Italy - hence the name.

At the time gold coins were minted because there was a shortage of silver and Parliament were worried that silver coins might run out - this florin was worth over 30 silver pennies.

This coin was found at a rally of metal detectorists by Andy Carter in a farmers field in north Norfolk.

"There were only three of us still looking - everyone else was packing up" Andy told the Guardian newspaper. "The coin was covered in mud, about 10 inches down. When I brushed off the soil, I saw the hind leg of a big cat.

"I thought: 'It can't be a leopard - they're as rare as hen's teeth.' I called one of the experts over and his eyes were on stalks."

An engraving from around 1355 from St Stephen's Chapel, Westminster, of King Edward III saying his prayers

Edward was crowned king of England when he was just 14 (Year 9!) and his reign of 50 years is one of the longest in English royal history.

"It is in very fine condition and retains light surface marks consistent with a field find," said Nigel Mills of auctioneers Dix Noonan Webb who are in charge of selling the coin.

"Only five are known to still exist and this is by far the finer of the two known specimens that have come to auction."

Two other coins are now in the British Museum and a third is at the Ashmolean Museum in Oxford.