
The Most Expensive Royal Engagement Ring Doesn’t Belong to Princess Diana or Meghan Markle
Royal family members Princess Diana and Meghan Markle often take the spotlight when it comes to royal engagement rings. However, the most valuable engagement ring in royal history belongs to someone outside of the House of Windsor. Their dazzling diamond far outshines the most famous royal jewels in elegance and cost.
The most expensive royal engagement ring belongs to Grace Kelly
The most expensive royal engagement ring belongs to Grace Kelly, the Hollywood actress who became Princess of Monaco. Kelly’s Cartier ring was given to her by Prince Rainier III in 1956.
Kelly’s ring featured a 10.48-carat emerald-cut diamond, flanked by two baguette-cut diamonds. It’s estimated to be worth at least $38.8 million today due to its size, quality, and historical significance.
Rainier initially proposed to Kelly with a simpler ruby and diamond eternity band. However, after seeing Hollywood’s penchant for lavish jewelry during Kelly’s film career, Rainier upgraded the ring.
The Cartier diamond not only symbolized their union but also cemented Kelly’s transformation from Hollywood royalty to a real-life princess. The sparkler made its film debut in Kelly’s final film, High Society.

Grace Kelly and Prince Rainier married on April 18, 1956, three months before High Society, was released by MGM in July 1956. Kelly had no intention of retiring from acting after her wedding; several years later, she even aspired to return to Alfred Hitchcock’s Marnie. Eventually, as Princess Consort of Monaco, a decision to quit acting was subsequently made.
How does Grace Kelly’s ring compare to other royal gems?
While Princess Diana’s iconic sapphire ring, now worn by Kate Middleton, carries immense sentimental value due to its significance in royal history, it’s estimated to be worth around $500,000 (per The Knot). Meghan Markle’s three-stone diamond engagement ring, featuring a center diamond sourced from Botswana and two side stones from Princess Diana’s collection, has an estimated value of $200,000.
Queen Camilla’s ring is estimated at $300,000-$400,000 (per Brides). It features a 5-carat emerald-cut diamond from the Queen Mother’s collection.
Sarah Ferguson’s engagement ring from Prince Andrew has a Burmese ruby surrounded by ten diamonds set in yellow gold (per Crisscut Magazine). Designed by Garrard, the same jeweler behind Princess Diana’s iconic sapphire ring, Fergie’s vibrant ring was reportedly valued at around $90,000 at the time of their 1986 engagement.
The couple’s daughter, Princess Eugenie, owns a rare Padparadscha sapphire, valued at approximately $120,000. Her sister, Princess Beatrice, has a 2.5-carat diamond ring, with .75-carat baguette diamonds on the sides, worth $80K (per Royal Central).
Who owns Grace Kelly’s ring today?

Grace Kelly’s iconic engagement ring is now part of Monaco’s royal collection. As one of the family’s most treasured heirlooms, the ring is occasionally displayed during special exhibits celebrating Monaco’s royal history.
The unparalleled value of Grace Kelly’s ring is due to its size, quality, and historical significance. The Cartier design’s timeless elegance continues to inspire modern engagement ring trends, standing as a testament to the grandeur of Monaco’s royal family.
While the exact individual responsible for its safekeeping is undisclosed, it is widely believed that Prince Albert II, Grace Kelly’s son and the reigning monarch of Monaco, oversees the family’s extensive collection of royal jewels. Following Kelly’s tragic death in 1982, the valuable piece remained with the family.
Grace Kelly and Prince Rainier were married for 26 years, from their wedding on Apr. 19, 1956, until Grace’s death on Sept. 14, 1982. They raised three children: Princess Caroline, Prince Albert, and Princess Stephanie.
Kelly died following a car accident near her home in Monaco. While driving with her daughter, Princess Stéphanie, Kelly reportedly suffered a stroke, causing her vehicle to plunge off a winding mountain road. She was rushed to the hospital but succumbed to her injuries the following day at 52.