One of the foremost historic diamonds – The Farnese Blue – will appear on the market for the first time in history this spring, after having remained in the same family for over three centuries. The 6.16-carat pear shaped blue diamond will be offered in Sotheby’s sale of Magnificent Jewels and Noble Jewels (15 May, Geneva) with an estimate of CHF 3.5 - 5 million (US$ 3,690,000 - 5,270,000).

Given to Elisabeth Farnese, Queen of Spain (1692-1766), the legendary diamond has subsequently passed down through four of the most important royal families in Europe: Spain, France, Italy and Austria.

Witness to 300 years of European history, from the aftermath of the Spanish Succession War to the fall of the Habsburg Empire, the diamond has travelled across the continent for centuries. And all this time, it was kept secretly in a royal casket. Excepting close relatives, and of course the family jewellers, no one knew of its existence.

THE FARNESE BLUE – A HISTORIC 6.16 CARAT PEAR-SHAPED FANCY DARK GREY-BLUE DIAMOND. ESTIMATE CHF3.5-5 MILLION ($ 3,690,000-5,270,000)

Blue has often been identified as the colour of kings and in the 17th and 18th centuries, blue diamonds were viewed as the ultimate royal gift. Like the famous Hope and Wittelsbach diamonds, the Farnese Blue was certainly found in the famed Golconda mines of India, which was the sole source of diamonds until the discoveries in Brazil in the 1720s.

David Bennett, Chairman of Sotheby’s International Jewellery Division and Co-Chairman of Sotheby’s Switzerland, said: “It is difficult to put into words the excitement of holding between thumb and forefinger a gem discovered centuries ago, knowing it originated in the legendary Golconda diamond mines of India. This stone has witnessed 300 years of European history, and in colour is reminiscent of historic Golconda blue gems such as the Hope diamond.”

Dr Philipp Herzog von Württemberg, Chairman of Sotheby’s Europe and Managing Director of Germany added: “With its incredible pedigree, the Farnese Blue ranks among the most important historic diamonds in the world. From the first minute I saw the stone, I could not resist its magic and as such, it is a huge privilege to have been entrusted with this sale.”