Editor’s Note
The Smithsonian has acquired one of the world’s rarest gems—a magnificent 2.33-carat Fancy Red diamond. This exceptional stone joins the museum’s famed collection and will be on public view starting April 1.
The Smithsonian National Museum of Natural History (NMNH) has announced that a 2.33-carat “Winston Red Diamond,” considered one of the world’s finest and among the largest known diamonds with the extremely rare “Fancy Red” color grade, has been added to its collection. It will be publicly displayed starting April 1 as part of the “Winston Fancy Color Diamond Collection,” which gathers some of the world’s rarest and most precious gems.
This diamond collection was donated by Ronald Winston, son of the renowned jeweler and collector Harry Winston. The museum’s National Gem Collection was itself founded in 1958 when Harry Winston donated the famous Hope Diamond to the Smithsonian Institution.
The Winston Red Diamond and the Winston Fancy Color Diamond Collection will be displayed in the museum’s Winston Gallery, offering visitors a remarkable opportunity to view one of the world’s premier collections of fancy color diamonds.
According to the museum, natural red diamonds are among the rarest gems on Earth, and “the Winston Red Diamond is a special one among them.”
The 2.33-carat gem is among the largest known deep red diamonds to receive the “Fancy Red” grade from the Gemological Institute of America (GIA), denoting extreme rarity. Experts estimate the odds of finding a Fancy Red diamond are less than 1 in 25 million, and the Winston Red Diamond is considered one of the most elegant in existence.
While color in some diamonds comes from impurity atoms trapped in the crystal structure, the museum explains that the deep crimson hue of the Winston Red Diamond is “the result of changes to the crystal caused by extreme pressure and heat deep within the Earth.”
A notable feature of this diamond is its old mine cut, an older cutting style than the round brilliant cut dominant in modern engagement rings. Characterized by larger, fewer facets, this suggests the stone was cut before the mid-1900s. Scientific and historical research findings on the Winston Red Diamond are scheduled to be published in the Spring 2025 issue of GIA’s quarterly journal, “Gems & Gemology.”