Three of the diamonds, which are step-cut and weigh 5.29 carats, 3.11 carats and 2.37 carats, form a brooch carrying a price estimate of $265,283 (GBP 200,000) to $397,924 (GBP 300,000), according to Bonhams, which will auction the jewel at its London Fine Jewellery sale on December 7.
In addition, a pair of ear clips featuring brilliant-cut diamonds of the same fancy color, weighing 2.08 carats and 1.93 carats, will be up for auction at the event, with an estimate of $66,320 (GBP 50,000) to $106,113 (GBP 80,000).
The diamonds’ story dates back to 1940, Jean Ghika, Bonhams’ director of jewelry for the UK and Europe, explained. That year, the present owner’s father-in-law, R.V. Cullinan, son of diamond magnate Thomas Cullinan, asked his friend General Pierre De Villiers, a director of De Beers, to buy some diamonds on his next visit to the mining city of Kimberley.
On the train back from De Beers’ Kimberley mine, General De Villiers bought a set of yellow diamonds off Sir Ernest Oppenheimer. He kept half and offered the other half — the ones now on sale at Bonhams — to R.V. Cullinan.
“It’s important to remember that only one in approximately 10,000 of all diamonds mined has a fancy color,” said Ghika.
“Fancy vivid yellow diamonds are some of the rarest in the world and the best examples are prized for their extraordinary vibrant tone and sun-like hue. They are increasingly sought after and we anticipate that they will attract a lot of interest from discerning collectors around the world,” she added.