Sherwood Forest is best known for the legend of Robin Hood - the outlaw who robbed the rich to give to the poor.

Now an amateur treasure hunter may have found his own fortune in the Nottinghamshire woodland.

A medieval ring discovered in the dirt and thought to date back to the 14th century, could be worth up to £70,000 ($87,000).

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A medieval ring discovered in the dirt of Sherwood Forest by an amateur treasure hunter and thought to date back to the 14th century, could be worth up to £70,000 ($87,000)

The artefact was discovered by Mark Thompson, who makes his living spray-painting fork lift trucks, had been in the famous Nottinghamshire woodland for just 20 minutes when his metal detector sounded.

The 34-year-old, who had only taken up the hobby 18 months before, was expecting to find something innocuous - perhaps some dropped money or rubbish left behind by holidaymakers.

But as he shovelled away at the soil he saw a glint of gold, and after removing the surrounding dirt he uncovered an ornate piece of jewellery which appeared to be adorned with a precious sapphire.

Mr Thompson has reported the find and it is now going through the treasure hunting process, which he hopes could end in him receiving a windfall.

He has consulted with auctioneers who have suggested it could be worth anywhere between £20,000 ($25,000) and £70,000 ($87,000).

Mr Thompson said: 'I had been out metal detecting with a group for about 20 minutes when I heard the signal.

'I was really excited when I saw that it was gold, but I didn't realise at that point just how significant it might be.

Amateur treasure hunter Mark Thompson uncovered the ring in the dirt (left) using a metal detector. It is believed the ring, which is engraved with an infant Christ on one side and a female saint on the other, dates from the 14th century.

A report into the ring by Dot Boughton, a regional finds liaison officer, compares the stone with one used on the tomb of former Archbishop of Canterbury William Wytlesey, who died in 1374

The ring was discovered covered in dirt in Nottinghamshire's Sherwood Forest, most well known for the legend of Robin Hood - the outlaw who robbed the rich to give to the poor

'I called my friend who came down to take a look and help see whether there was anything else related nearby.

'It's the find of a lifetime - I never expected to unearth anything like that. I'm still in shock when I think about it - it was such an exhilarating moment.

'If it does prove to be as valuable as we think it might be, it would completely change my life.

Mark Thompson, 34, who makes his living spray-painting fork lift trucks, found the ring after just 20 minutes in the forest

'I'm renting at the moment and I'd love to be able to buy a house or move into somewhere more comfortable.'

Dot Boughton, a regional finds liaison officer, confirmed that the ring is undergoing tests at the British Museum and the case has been referred to the coroner so it can be formally classified as treasure.

It is believed the ring, which is engraved with an infant Christ on one side and a female saint on the other, dates from the 14th century.

Ms Boughton's report into the ring compares the stone with one used on the tomb of former Archbishop of Canterbury William Wytlesey, who died in 1374.

Mr Thompson is now waiting for the coroner to set a date for an inquest to confirm the ring is treasure.

If it is, it will be valued by experts and offered to museums to purchase. Mr Thompson will receive the reward as the finder.

Another amateur treasure hunter, who unearthed a precious Tudor ring in North Yorkshire, recently received a five-figure sum for his find.

The 15th century ring was 80 per cent gold, containing a ruby and an emerald.

Lee Rossiter found the Green Hammerton Ring in North Yorkshire, using a cheap metal detector he had bought on eBay.