The Duchess of Cambridge performed her first official engagement today as the Honorary Air Commandant of the Air Cadets, attending a service to mark the organization’s 75th anniversary. She wore an Alexander McQueen coat and a piece of jewelry long associated with the Air Cadets: the Dacre Brooch.

The brooch, which is set with diamonds and other gemstones, was traditionally presented each year to the best female cadet. That tradition began in 1982, the year that women were first admitted to the Air Cadets, and continued until last year. It was decided that the best female cadet should, like her male counterpart, instead receive the Dacre Sword.

Newspapers interviewed the last female Air Cadet to wear the brooch. She noted, “It is quite an honour. I was the last cadet to wear it, and now she is wearing it. It is the best accessory.” The brooch is named in honor of the late Air Commodore G.B. Dacre and his wife, Elizabeth, who presented it to the Air Cadets in 1982.

Papers also reported that the brooch had been gifted to Kate, but I’m not sure whether it was offered to her as a personal gift or presented to her to wear during her tenure as the organization’s patron. The brooch was reportedly presented to Kate by the Air Cadets after she was appointed as their newest patron. The role was passed along to Kate by the Duke of Edinburgh, who is slowly scaling back his workload ahead of his upcoming 95th birthday.