Exclusive: Royal-Favorite Jeweler Kiki McDonough Shares Memories of Princess Diana and Working With "Three Generations" of Royalty

If you've looked at a photo of the Princess of Wales in the past decade, chances are you've seen Kiki McDonough's colorful gemstone jewelry. The Princess of Wales owns at least 20 pieces from the celebrated British jeweler, and after celebrating her 40th anniversary of being in business this year, McDonough is sharing the secrets behind her success with Marie Claire.

"What is so nice for me is that three generations of royalty have worn my jewelry," she says. "I feel very lucky." Princess Diana was a fan of McDonough's accessibly elegant designs, and the jeweler recalls the unexpected moment when the late royal first stopped by.

"I remember the day Diana visited the shop," she says. "I was in the kitchen making a cup of coffee and the builder who was working there said, ‘The Princess of Wales is knocking at the door,’ and I thought he was joking. Soon after that she wore our earrings to meet former First Lady Barbara Bush."

Sarah Ferguson also wore McDonough's designs in the '80s, sporting the designer's earrings in her engagement photo shoot with Prince Andrew.

Today, Princess Diana's daughter-in-law, Princess Kate, wears Kiki McDonough's rainbow-hued gemstones for both formal and everyday occasions. It's an approach to fine jewelry that McDonough tells Marie Claire is important to her as a modern working woman.

"I have always designed jewelry that reflects my own lifestyle, while also celebrating and exploring my passion for the stones," she says. "I live a very full life, like lots of other people. I am a working mother rather like the Princess of Wales, and I believe my designs are perfect for that. I don’t do bling or cutting-edge trends; it’s elegant, pretty jewelry that makes you feel good."

This philosophy, however sensible it seems, set McDonough's designs apart when she first started out in the business. A pair of McDonough's crystal heart earrings are on display at London's VA museum, and the designer admits, "When I first created them, I didn’t have the faintest clue what I was doing," telling Marie Claire that the idea came to her "in the first six months of the business."

"It was by complete chance they became a hit—nobody was more surprised than me," she said. "At that time, no one else was doing fine jewelry for women to buy for themselves, so it was truly all a shot in the dark."

Having served generations of the Royal Family, McDonough reflects on the changes in royal jewels over the years. "Over time, elaborate, formal jewelry has become increasingly reserved for official state events, while daily royal attire has evolved to become more relaxed and understated—beautiful yet practical for everyday use," she says, adding, "Today, it is increasingly common to see fine jewelry that is suitable for everyday wear."

To mark the 40th anniversary of her business, McDonough has written a book, Kiki McDonough: A Life of Colour, which will release in the United States on July 29.

"I kept thinking it was a crazy idea, but finally I gave in," McDonough says of the coffee table book, which is packed with stunning photos of her work. "I’m great at looking forward, and not so good at looking back, so it was very nice to revisit the past in this way, seeing all the happy memories, and realizing that many of the pieces I created 40 years ago still sell today."

Reflecting on the challenges she faced in the earlier days of her career, McDonough shares, "In the early '90s I was steering my business through a recession, and I had a baby and a two-year-old. I often wonder how I managed to keep going—perhaps it was sheer determination, resilience, and a good sense of humor. Without those, I might have been overwhelmed and given up."

Looking to the future, the jeweler—who has designed some special anniversary pieces this year—says she's hoping to spend more time in the States. "I love America, and although we have a huge online presence there, I would love even more Americans to wear my jewelry!" she says.