"Set with diamonds, sapphires, rubies and emeralds, the bejewelled piece features the cypher of her father, King George VI," Zack Stone, a fine jewelry expert from U.K. retailer Steven Stone, shared with WWD.

Trooping the Colour — the annual celebration of the monarch’s official birthday — Queen Camilla embraced timeless elegance. In honour of this year's festivities, the royal opted for an understated ensemble,

Trooping the Colour in the U.K. is a celebration of the reigning monarch's birthday. It's held every year in June, regardless of when their actual birthday is, and it involves a lot of fanfare with a parade and a dramatic RAF flyover.

King Charles and Queen Camilla appeared at the annual Trooping the Colour celebration as the monarch continues to undergo treatment for cancer.

Lip reader, Nicola Hickling, has claimed that King Charles made a brutal 'dig' about Prince Harry to Queen Camilla during the Trooping the Colour event.

While celebrating the monarch’s birthday with the annual Trooping the Colour in London on Saturday, Prince Louis, 7, gave an enthusiastic greeting to the crowd.

Senior working royals including Prince William, Kate Middleton, Princess Anne, Prince Edward and Queen Camilla will reportedly take part in the king's birthday parade.