The Duke of Buccleuch launched the exhibition last week at his Bowhill House home.

Some fifty jewel-like portrait miniatures, taken from the world-renowned Buccleuch Collection, include a few never-before-seen pieces and will be on display for the rest of the month.

The collection – co-curated by His Grace and Dr Stephen Lloyd, former Senior Curator of the Scottish National Portrait Gallery and an international authority on portrait miniatures – will be exhibited at Bowhill using the latest display cabinets and lighting techniques, allowing the miniatures to be seen in their proper glory for the first time.

A spokeswoman for Bowhill House said: “The collection included in the exhibition contains the famous unfinished portrait of Oliver Cromwell by Samuel Cooper and fine examples of the art form, dating back to the 1520s including a masterpiece by Hans Holbein.

“Subjects depicted in the portrait miniature collection range from Kings and Queens to cats and dogs, displaying the versatility and brilliant eye for detail of these extraordinary skilled artists.” The Buccleuch Collection of portrait miniatures reflects the passion of Walter Francis, the 5th Duke of Buccleuch (1806-1884), and of his wife Charlotte Anne.

They were enthusiastic collectors in general, adding quantities of silver, French furniture, Sèvres porcelain and important paintings.

But miniature portraits was a particular passion.

The couple’s interest was strong and was continued by their son William, 6th Duke of Buccleuch (1831-1914).

Although some sales to British institutions during the 1940s reduced the size of the collection slightly, it still contains more than 750 examples.

Particularly strongly represented are 16th and 17th century English portrait miniatures.

During the nineteenth century, when most of the miniatures were being acquired, attributions both to artists and identifications of sitters were often confidently given in a way that modern scholarship has questioned. Much work is still being undertaken in this area and it is possible that some of the miniatures on display, where the sitter is described as 'unknown’, will one day be identified.

The Buccleuch Collection miniatures will be on display everyday at Bowhill House until July 31.