A reward has been offered for the return of the coins to their owner
A £50,000 reward has been offered for the return of a "unique" collection of Scots coins stolen last year.
They were taken from the home of Lord and Lady Stewartby at Broughton in the Borders and are worth about £500,000.
The items have been described as the most important collection of early Scottish coins ever assembled with some dating back nearly 900 years.
A reward has now been offered for any information which leads to the return of the coins to their rightful owner.
The theft took place overnight between 6 and 7 June 2007.
The collection had been amassed by Lord Stewartby over a period of some 50 years.
Nick Holmes, senior curator of numismatics at the National Museum of Scotland, said the coins were of huge importance.
"This collection is a unique part of Scottish history and the impact of its loss cannot be overstated," he said.
Police suspect the involvement of organised crime in the theft.
Their enquiries have led them to believe that a gang from the west of Scotland with underworld links may have been involved.
Although a "significant enquiry" has been carried out in respect of the theft, police are issuing a fresh appeal to the public for help in tracing the coins.
A police spokesman said: "The coins are unsellable on the market because they are so well known, and dealers and others in the coin trade have been checking the source of any early Scottish coins that appear for sale.
"We are hoping that the prospect of a £50,000 reward may help jog the memories of those who could help us in our enquiries.
"We would urge anyone with any information about the whereabouts of these coins to contact police immediately."
Information can also be left on the confidential Crimestoppers phone line.