A Cartier bracelet once owned by Queen Victoria Eugenia of Spain (1887-1969) will sparkle at an upcoming jewellery auction in Geneva.
The conch pearl, enamel and diamond bracelet, produced in the 1920s, is expected to make up to $1.4m when it auctions at Sotheby's Magnificant Jewels sale on November 14.
It has been consigned by a member of the Spanish royal family.
Its considerable eye appeal, allied with its royal provenance, should ensure it has plenty of suitors.
David Bennett, the chairman of Sotheby's jewellery department for Europe and the Middle East, said that the bracelet was a "unique, sumptuous, and truly royal bracelet - unquestionably one of the greatest jewels designed by Cartier during the 1920s."
The granddaughter of Queen Victoria and grandmother of current Spanish king, Juan Carlos, Eugenia was known for her extensive jewellery collection.
Several other Cartier pieces will also be up for grabs, including a $500,000-estimated 1930s platinum and diamond bracelet, as well as a diamond double clip brooch featuring pear-shaped stones, which is valued at $250,000.
The star of the show, however, could well prove to be a pair of 1921 ruby and diamond pendent earrings, gifted to HSH Princess Max Egon zu Hohenlohe-Langenburg (1892-1990) as a wedding present from her parents.
Featuring an 11-carat Burmese ruby on each earring, the pair is expected to achieve up to $2.5m.
Sotheby's rival Christie's will be hosting its own Geneva jewellery sale the previous day.
It will feature the famed Archduke Joseph Diamond, which is expected to achieve in excess of $15m.