A diamond and pearl bracelet once owned by the Queen’s sister Princess Margaret has sold at auction for almost £400,000.

The art deco piece was famously worn by Margaret for her 19th birthday photograph taken by celebrated photographer Cecil Beaton in 1949.

It was bought by an undisclosed private bidder for £396,800, including buyer’s premium, during the sale at auction firm Dix Noonan Webb’s Mayfair saleroom in central London.

Frances Noble, the company’s associate director and head of the jewellery department, said of the sale price: “It not only reflects the strength of the current auction market but also the overriding importance of provenance.

“Princess Margaret was photographed wearing this bracelet on numerous occasions which certainly added to the appeal of the piece, attracting international interest and extremely competitive bidding – an exceptional result for the vendor.”

The bracelet had been sold by Christie’s in 2006 in their auction of jewellery from the princess’ collection following her death four years earlier.

It dates from about 1925 and features a double row of cultured pearls bordering a line of circular-cut diamonds.

Beaton’s picture of Margaret was taken on July 8, 1949, and published on her birthday – August 21.

Writing about the sitting in his diary, he said: “She was at Lords for the Eton and Harrow match, and got back a bit late but she is such a quick dresser that a few moments after her return she appeared changed into the new evening dress Hartnell had supplied her that morning – a dull dress of white tulle embroidered with sequin butterflies and a rainbow tulle scarf around the waist.

“She looked very pretty and wore quite a lot of make-up – and the eyes are of a piercing blue – catlike and fierce and so very pristine and youthful.”