Historic Diamonds / Famous Diamonds
An Inside Look at the Bulgari Laguna Blu, the Most Valuable Bulgari Gem Ever Sold
By Grant Mobley, Updated: September 25, 2025
This ultra-rare blue diamond sold for over $25 million.
Priyanka Chopra Jonas wears the Bulgari Laguna Blu to the 2023 Met Gala at The Metropolitan Museum of Art on May 01, 2023 in New York City. (Getty Images)
The Bulgari Laguna Blu made headlines in 2023 when it sold at Sotheby’s Geneva for over $25 million, cementing its place as one of the world’s most extraordinary natural treasures.
At 11.16 carats, the natural ‘fancy vivid blue’ diamond remains the most valuable gemstone ever sold by Bulgari and is considered a rarity three times over: first, for its exceptional color and size; second, for being mounted by Bulgari in 1970 at the height of its creative era; and third, for having remained unmodified and unseen since its original commission. Recognized by the Gemological Institute of America (GIA) with the highest and rarest color grade for a blue diamond, the Bulgari Laguna Blu continues to stand among the most celebrated jewels in modern history.
Meet the Expert
- Grant Mobley is the Jewelry & Watch Editor of Only Natural Diamonds.
- He is a GIA Diamonds Graduate.
- He has over 17 years of jewelry industry experience, starting with growing up in his family’s retail jewelry stores.
Ahead, discover the remarkable story behind this legendary stone, from its Bulgari origins to its record-breaking moment at Sotheby’s—and why natural blue diamonds like the Laguna Blu are among the rarest treasures on Earth.
The Bulgari Laguna Blu: An Extraordinary Gem
Olivier Wagner, Head of Jewellery at Sotheby’s Geneva, says, “The Bulgari Laguna Blu is an extraordinary gem in every way. At 11.16 carats, this unmodified pear-shaped blue diamond has received the highest grade for a blue diamond by the Gemological Institute of America, acknowledging its mesmerizing color and hue. This true wonder of nature was selected by Bulgari, the prestigious Roman Jewellery Maison, over fifty years ago to create a ring for a discerning private collector who has kept it ever since.”
She continues, “The Bulgari Laguna Blu diamond is bound to become the object of any collector’s dream, and we are delighted that it will be first premiered at the always highly anticipated Met Gala’s red carpet.” The Bulgari Laguna Blu was worn at the 2023 Met Gala by Bulgari’s global Ambassador, Priyanka Chopra Jonas, where it was reset into a striking necklace for the occasion.
Why Blue Diamonds Are Exceptionally Rare
Any blue diamond is among the most elusive natural color diamonds on the planet. Blue diamonds are not just created by the forces of nature that form other natural diamonds. Rather, they are born out of an even more fortuitous happenstance – the presence of the trace element boron within the diamond’s carbon structure during its formation deep within the Earth, much deeper than where most other diamonds form.
Blue diamonds of any size are incredibly rare, but those that surpass 10 carats are unfathomably rare. A blue diamond that qualifies as Fancy Vivid, the brightest and most sought-after hue a blue diamond can exhibit, and exceeds 10 carats in weight, is jaw-dropping. Fewer than ten comparable diamonds have surfaced at auction houses worldwide over the last few decades. ‘The De Beers Blue,’ at 15.10 carats, sold for over $56 million, and the ‘Blue Moon of Josephine,’ at 12.03 carats, sold for over $48 million.
Bulgari’s Mastery and the Original 1970 Commission
This exceptional diamond was originally mounted as a ring by Bulgari for a very special commission from the original owner in 1970. At that time, Bulgari was already basking in the glow of its high-profile clientele, which included legendary icons like Elizabeth Taylor, Ingrid Bergman, Anita Ekberg, and Sophia Loren, just to name a few. Bulgari was already known for its daring use of color, blending precious and colored stones in bold and unexpected ways. And the Laguna Blu was no exception.
The jeweler mounted this unmodified diamond into an elegantly pared-down ring that allowed the stone to shine in all its glory, showcasing the brand’s ability to maximize the natural beauty of an exceptional diamond. Maybe most impressively, the Laguna Blu has remained in the same family since its original commission in 1970, meaning that it has only been seen by a select few since its creation. Also, with diamond-cutting technology much improved in the fifty years since this diamond was cut, this unmodified stone may still have some hidden potential waiting to be unleashed.
Other Famous Blue Diamonds
Together with these record-breaking stones, the Bulgari Laguna Blu finds itself in good company among the most important blue diamonds ever to appear on the world stage.
The most legendary of all is the Hope Diamond, a 45.52-carat Fancy Deep Grayish-Blue gem whose ownership spanned French royalty to American heiresses. Today it resides at the Smithsonian Institution in Washington, D.C., where its beauty and rumored curse continue to captivate millions.
The Wittelsbach-Graff Diamond, a 31.06-carat Fancy Deep Blue once part of the Austrian and Bavarian crown jewels, set a record when Christie’s sold it in 2008 for over $24 million, cementing its place in European history.
The Okavango Blue, discovered in 2018 at Botswana’s Orapa mine, is a 20.46-carat Fancy Deep Blue diamond. Retained as a national treasure, it symbolizes Botswana’s natural heritage and global diamond leadership.
The Mediterranean Blue, a 10.03-carat Fancy Vivid Blue, dazzled collectors when it appeared at Sotheby’s High Jewelry Sale in Geneva in May 2025, underscoring the insatiable demand for top-quality blue diamonds.
The Mellon Blue, a 9.51-carat Fancy Vivid Blue diamond once owned by philanthropist Rachel Lambert Mellon (also known as Bunny Mellon), sold at Sotheby’s in 2014 for $32.6 million, breaking auction records at the time. It will return to the auction block at Christie’s Magnificent Jewels auction in Geneva in November 2025, where it could break records once again.
Sotheby’s Geneva Luxury Week Auction
The Bulgari Laguna Blu ultimately sold for over $25 million at Sotheby’s Geneva Luxury Week in May 2023, setting a benchmark as the most valuable gemstone ever sold by Bulgari. It was part of a wider collection by the same consignor that included two additional Bulgari white diamonds from the early 1970s—a 12.08-carat pear-shaped stone and an 18.78-carat step-cut—as well as a fourth piece, an 8.33-carat pear-shaped white diamond signed Pederzani. The collection was exhibited at the Mandarin Oriental in Geneva before going under the hammer during Sotheby’s Luxury Week sale.
