Christie's will present the Ocean Dream diamond at its Magnificent Jewels auction in Geneva on May 13, 2026, bringing one of the world’s rarest coloured diamonds back to the auction market after 12 years.
The 5.50-carat fancy vivid blue-green diamond is regarded as the largest diamond of its kind ever graded by the Gemological Institute of America (GIA). Christie’s has placed an estimate of CHF 7 million to CHF 10 million on the stone, which will headline the auction at the Four Seasons Hotel des Bergues in Geneva.
Known as the Ocean Dream, the triangular-cut stone was fashioned from an 11.70-carat rough diamond discovered in Central Africa during the 1990s. The gem is classified as a Type Ia diamond and has been recognized for its rare natural blue-green colour saturation, a combination seldom seen in natural diamonds.
The diamond first gained global attention in 2003 when it was exhibited at the Smithsonian Institution’s “Splendor of Diamonds” exhibition in Washington, D.C., alongside several historically important coloured diamonds. Christie’s stated that the Smithsonian described the Ocean Dream as one of the eight rarest diamonds in the world.
This will mark only the second time the stone has appeared at auction. Christie’s previously sold the diamond in Geneva in May 2014 for approximately CHF 7.7 million. Since then, it has remained in a private collection.
According to Christie’s, previews for the Ocean Dream are scheduled to take place in Bangkok, Hong Kong and Geneva ahead of the auction. The diamond is currently mounted in a ring featuring additional fancy-shaped white diamonds and an interchangeable setting incorporating rock crystal and pink diamonds.
The upcoming sale reflects continued global demand for rare natural fancy colour diamonds, particularly stones with unusual colour combinations and limited market availability.
