The Diplomatic Corps Reception is arguably the most highly anticipated annual event on the royal calendar. The white-tie affair is one of the few times during the year the ladies in the family don the spectacular royal jewels — and Queen Camilla sparkled in the late Queen Elizabeth II’s rarely seen Aquamarine Ribbon Tiara

"The Princess is feeling positive about the future and very much looking forward to representing the royal family at the state visit and beyond," a source told The Mirror prior to the Emir's arrival.

Queen Camilla, who is recovering from pneumonia, posed for photos with the Amir of Qatar alongside King Charles on Tuesday, Dec. 3, before the royal family hosted a state banquet for the guests of honor.