The 8 Most Expensive Royal Engagement Rings, Ranked by an Expert

There's no denying the intriguing appeal of celebrity engagement rings. Just this summer, the likes of Scarlett Johansson, Sarah Hyland, and Kristen Wiig all revealed their newly acquired rings, each one of them unique and beautiful. But if you ask me, Hollywood's engagement rings can't quite compete with those of royals around the world—especially considering the life-altering, weighty importance of marrying into a royal family and taking on a new set of global duties. 

To offer expert insight into the most expensive royal engagement rings, I tapped Kathryn Money, VP of strategy and merchandising for Brilliant Earth, a company that specializes in ethically sourced fine jewelry (going well beyond just conflict-free diamonds). I supplied Money with a list of my eight favorite royal engagement rings and she shared her estimated price for each ring, along with fun facts you might not have known. Scroll down to see how the Brilliant Earth executive ranks the most expensive royal engagement rings. 

8. Queen Letizia of Spain: $20,000 to $25,000

"Queen Letizia's non-traditional ring does not include a center diamond or gemstone," Money says. "Instead, her sophisticated band features 16 vertically set baguette-cut diamonds in a white gold channel setting. Depending on the quality and specific characteristics of the diamonds, we estimate the cost of the ring at approximately $20,000 to $25,000." 

7. Crown Princess Mary of Denmark: $25,000 to $35,000

"Crown Princess of Denmark Mary's original engagement ring featured an estimated one and a half–carat emerald-cut diamond flanked by two emerald-cut rubies, and since her wedding, she has added two additional diamond baguettes on either side of the rubies," Money told Who What Wear. "Crown Prince Frederik chose the ring to represent the colors of the Danish flag. Depending on the quality and specific characteristics of the diamond and gemstones, we estimate the cost of the original ring at approximately $25,000 to $30,000."

6. Princess Eugenie: $30,000 to $50,000

"Similar to her mother's famous ring, which featured a Burmese ruby surrounded by diamonds, Princess Eugenie's engagement ring features a unique pinkish orange-hued Padparadscha sapphire with a distinctive floral halo of pear and round brilliant diamond accents on a Welsh gold band," Money says. "We estimate that the center stone is a 3-carat oval brilliant Padparadscha sapphire, surrounded by pear and round diamonds totaling about two and a half to three carats. We estimate that Princess Eugenie’s feminine and vintage-inspired ring costs approximately $30,000 tp $50,000, depending on the quality and specific characteristics of the gemstones."

5. Princess Charlene of Monaco: $55,000 to $65,000

"Prince Albert proposed to Princess Charlene with an impressive ring featuring a three- to four-carat pear-shaped diamond as the center stone," Money told Who What Wear. "The elegant ring is accented with round diamonds cascading down the shoulders of the band, creating a uniquely royal look. We estimate that Princess Charlene’s ring costs approximately $55,000 to $65,000, depending on the quality and specific characteristics of the diamonds."

4. Camilla Parker Bowles: $70,000 to $100,000

"The gorgeous art deco style ring Prince Charles used to propose to Camilla in 2005 features a lovely five-carat emerald-cut diamond in the center, flanked by three diamond baguettes on each side," Money says. "We estimate replicating this royal family heirloom would cost approximately $70,000 to $100,000, but since the ring once belonged to the Queen Mother, Prince Charles's grandmother, it is priceless due to its cultural significance."

3. Meghan Markle: $120,000+ 

"Prince Harry custom-designed Meghan's engagement ring, featuring a five-carat center cushion cut diamond framed by two 0.75 carat round diamonds from Princess Diana's personal collection," Money says. "Updated from its original plain band style, the gorgeous trio of diamonds are now set in a thin micro-pavé band. The center stone's Botswana origin is reflective of Prince Harry and Meghan’s personal connection to the country and their shared commitment to social and environmental responsibility. Our estimated cost to replicate the look of this ring would be upward of $120,000, assuming a five-carat cushion-cut center diamond with rare, high-quality characteristics. However, given the use of Princess Diana’s heirloom diamonds as the side stones, this ring is truly priceless."

2. Grace Kelly: $550,000+ 

"The Cartier engagement ring chosen by Prince Rainier III of Monaco for Grace Kelly featured an emerald-cut center diamond weighing in at an estimated 10.5 carats," Money told us. "Set in platinum with two baguette accent diamonds, this exquisite ring reflects Grace Kelly’s sophisticated style perfectly. We estimate that Princess Grace of Monaco’s ring would cost $550,000 or more to re-create, but the iconic original is priceless."

1. Kate Middleton: Priceless

"Kate Middleton’s exquisite engagement ring, featuring a deep blue 12-carat sapphire surrounded by a halo of 14 round diamond accents set on an 18K white gold band, was originally selected by Princess Diana in 1981 shortly after accepting Prince Charles's proposal. The stunning design is reminiscent of a brooch Prince Albert had custom made for Queen Victoria before their wedding in 1840. The historical and cultural significance of Kate's ring makes its value very difficult to estimate, and we would contend that the ring is priceless."

Next, I spent four hours on Etsy finding the best vintage jewelry picks.