The Princess of Wales (formerly known as Kate Middleton) attended the 2025 Irish Guards’ St. Patrick’s Day Parade at Wellington Barracks in London. Fans were delighted to see the royal there as she had to miss last year’s celebration due to her battle with cancer. But after announcing in January that she was in remission and returning to work, the princess made sure she was on hand for all the festivities this year.

Kate, who is the honorary Colonel of the Irish Guards, wore a forest green Alexander McQueen coat with a matching-colored felt beret by Awon Golding for Lock & Co. She accessorized her outfit with a fan-favorite gold shamrock brooch. Because we’ve seen her wear that accessory for the occasion before, many just assumed it came out of her jewelry box. But that’s not the case since the brooch isn’t Kate’s.

Here’s who it belongs to and how much it actually cost.

Who owns the fan-favorite piece of jewelry Kate has worn for several years?

The lovely brooch does not belong to Kate or any other royal. It’s owned by the Irish Guards and loaned to members of the family to wear during St. Patrick’s Day celebrations.

The jewelry experts at the U.K. retailer Steven Stone took a closer look at the piece and its history.

“Loaned to members of the royal family by the Irish Guards in celebration of St. Patrick’s Day, Kate first wore her shamrock brooch in 2011 and is reported to have exclusively worn it since then,” Maxwell Stone shared. “Believed to have been designed by Cartier, the piece is made from 18-carat yellow gold and features a tiny, single emerald at the center of the textured leaves.

“Previously worn by the Queen Mother and Princess Anne also, Kate has worn the brooch on several visits to Northern Ireland as well as to St. Patrick’s Day celebrations. The brooch no doubt holds further significance for Kate, as it’s the first brooch that she ever wore in an official capacity as a royal. I’d estimate this simple yet stunning brooch to be worth $3,000.”

When the princess became the honorary Colonel of the Irish Guards

As mentioned, Kate is the honorary Colonel of the Irish Guards. The late Queen Elizabeth II appointed Prince William to the position in 2011, shortly before he married Kate and the couple attended many of the regiment’s St. Patrick’s Day parades together.

But after the monarch’s death, King Charles III needed to switch up a number of roles for some family members and named Kate the ceremonial Colonel of the Regiment.

In a speech following her appointment, the princess said: “I am here to listen to you, to support you, and to champion you in all you do — this is a responsibility I do not take lightly.”