A memorial in the shape of a sundial is to be set up as a tribute to the late Queen Mother at one of her favourite museums.

It will be placed in the grounds of the Bowes Museum at Barnard Castle, Co Durham, which she visited regularly for most of her life.

It has been commissioned by the Friends of the Museum, of which she was patron for 40 years. It will be delivered later this year, and it is hoped a member of the Royal Family will formally unveil it next spring.

Lesley Taylor, chairman of the Friends, said yesterday, "The Queen Mother gave the museum wonderful support for many years. She took a keen interest in what was going on, rather than just being a figurehead.

"She helped out in many ways behind the scenes as well as performing public duties. We wanted something really special as a memorial to her, and feel the sundial will be just that."

The Queen Mother first started calling there as a young girl when she spent summer holidays with her parents, the Earl and Countess of Strathmore, at Streatlam Castle, five miles away.

When she became the patron she told staff during her visits that she loved studying the paintings, porcelain, furniture and other art treasures, and only wished she could spend more time there.

The sundial will be in the form of an armillary sphere made of marine grade surgical steel mounted on a plinth of stone from Dunhouse Quarry near Barnard Castle, which provided the stone for the building itself over a century ago.

It is being made by sculptor David Harber of Oxfordshire. The cost has not been revealed.

An inscription will include the Latin phrase Hora Transit Manet Amicitia, which translates as "The hour passeth, friendship endureth."

Details will be given about the distances to the Queen Mother's residences, including Streatlam Castle, Glamis Castle and the Castle of Mey in Scotland and Clarence House in London.