A GOLD ring has been found on the grounds of a Scottish castle after lying in the ground for 500 years.

The ring, built around an oval-shaped purple stone, was discovered atop a molehill at Dundonald Castle in South Ayrshire.

It now forms a part of the National Museums of Scotland collections after being reported by Historic Environment Scotland, the castle's owners.

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The stone at the centre of the ring is believed to be made from amethyst, and the piece is thought to have been made by a goldsmith in Scotland or England in the late 1400s or early 1500s.

The band of the ring is carved with folate designs, with one side featuring what appears to be a vine while the other shows a stem with seven spiky leaves.

An expert has described the ring as an "elite object", that could have been believed to provide "protective qualities" for the wearer.

Dr Georgia Vullinghs, National Museums Scotland’s curator of Renaissance and early modern history, told The Times: “It is a beautiful example of Renaissance stone-set jewellery from Scotland and enhances our current collection.

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“Based on the style of the ring, we can date it to the late 15th, early 16th century.

“The ring comprises a gold band set with a single polished oval pink-purple coloured stone, likely amethyst. The stone may have been believed to hold protective qualities for the wearer.

“This is certainly an elite object. The ring likely belonged to one of the residents of the castle, or a visitor, during the 16th century."

Dundonald Castle has seen several archaeological excavations in recent yearsDundonald Castle has seen several archaeological excavations in recent years (Image: Society of Antiquaries)

Vullinghs also described the find as "remarkable", and said it could have represented many different things to its owner, such as a gift from a loved one or a symbol of faith.

The piece was found by a a member of Friends of Dundonald Castle, which runs Dundonald Castle for HES.

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They said it was “unearthed by a mole and was poking out of its molehill in front of the castle”.

Dundonald Castle hosted the launch of a campaign to celebrate Scotland's archaeological importance earlier this year.

It has seen several archaeological excavations in recent times, with finds including stone blades, jewellery and ancient coins.

The discovery came to light after Robin Laing, an author, songwriter and poet, heard about it while researching a recent book.

He wrote a poem, titled The Dundonald Ring, about the find.

Laing said: “You can learn a lot about a castle from the guidebooks but there’s no substitute for actually going.

"I spoke to the custodians who happened to mention the discovery of this ring and what was amazing was that it was found on top of a molehill, with the sun glinting off it.

“That ring was lost for centuries and it was a mole that brought it to the surface. It’s a remarkable story.”