The earliest known coin to be minted in Scotland almost 900 years ago has been acquired for the nation after it was found by a metal detectorist.

The medieval David I silver coin, discovered in a wooded area near Penicuik, Midlothian in 2023, has been dated to the second half of the 1130s.

As required by law it was reported it to Treasure Trove and allocated to National Museums Scotland (NMS) by the Scottish Archaeological Finds Allocation Panel.

The coin was valued at £15,000, which was paid to the finder as a reward by the King’s and Lord Treasurer’s Remembrancer.

The NMS said it would be used for research but it is hoped it will go on display in future.

King David I of Scotland, who reigned from 1124 until 1153, introduced the country’s first coinage.

Alice Blackwell, senior curator of medieval archaeology and history, said it was thought all his earliest coins were created in a mint in Carlisle, Cumbria, which he took control of in the 1130s.

But she added: “This coin is really significant because it’s the first of that earliest type, the earliest coins to actually have been minted outside of Carlisle.

“It was minted in Edinburgh, so it’s the first time that we have Scottish coinage being minted in what was a core part of the Scottish kingdom.”

She said any coins found before the king’s reign could be Roman Age, Viking Age or medieval coinage.

David I later lost control of Carlisle.

The coin found in Midlothian has a portrait of the monarch’s head on one side and a cross-based design on the other.

It also bears an inscription which indicates it was minted in Edinburgh.

The discovery will help experts expand their understanding of how and where coins were minted in medieval times.

Dr Blackwell said there was virtually no documentary sources that explained how coinage was produced in Scotland.

She added: “The coins themselves are the primary source.

“This is the first time that we can see this very early minting of coinage in Edinburgh.”

The expert added the first Scottish coins were quite rare.

She also said the discovery of another had the potential to increase understanding about how the first coinage was produced and how it began to be used in Scotland.

Later in the reign of King David I, coins were minted in places including Perth, Berwick-upon-Tweed, Aberdeen, St Andrews, and Roxburgh in the Scottish Borders.

As well as introducing Scotland’s first coinage his reign included the foundation of royal burghs such as Perth, Dunfermline and Stirling, and the reorganisation of civil institutions.