A Cartier aquamarine and diamond brooch dating from 1932 and purchased by Her Majesty Queen Elizabeth the Queen Mother from the celebrated jewellers on January 23, 1947 for £175, will be offered for sale by Dix Noonan Webb in their auction of Jewellery, Watches and Objects of Vertu on November 23.

Engraved with the ownership mark ‘M’ beneath Princess Margaret’s coronet, it is estimated to fetch £40,000-50,000.

The brooch was formerly from The Collection of Her Royal Highness, The Princess Margaret, Countess of Snowdon and was sold at Christie’s in June 2006.

Frances Noble, Head of the Jewellery Department and Associate Director at Dix Noonan Webb, explained: “Princess Margaret’s love of brooches was evident throughout her life, and this particular brooch seems to have been a favourite, as there are numerous photographs of her wearing it throughout her life. Known for her sense of fashion and style, Princess Margaret always coordinated the brooch to match her outfits, seemingly always in shades of blue. In 1950, at the age of 20, she was photographed wearing this brooch with a stunning strapless ballgown in ice blue brocade, at a dance at the Dorchester Hotel.