Queen Camilla is ringing in her birthday at work, but the job comes with a totally royal look.

The Queen turned 77 on July 17, and she spent the day with King Charles at the second State Opening of Parliament of his reign in London. Continuing tradition, the royals dressed up to meet the grandeur of the occasion, with Queen Camilla wearing a white gown and the George IV State Diadem plus plenty of diamonds.

As she arrived at the Palace of Westminster Queen Camilla wore a white gown with long sleeves and embroidery accenting the cuffs, skirt and hem.

Topping off the regal ensemble was the George IV State Diadem, which she had worn once before.

King Charles’ wife made her debut in the historic headpiece, otherwise known as the Diamond Diadem, for the first State Opening of Parliament of his royal reign in November 2023. The sparkler glitters with 1,333 diamonds and has a rich history. The regal head-topper was made for the coronation of King George IV in 1820 and is what the monarch wore (along with a large purple velvet cap) on his way to Westminster Abbey for his crowning ceremony over 200 years ago.

The Diamond Diadem has since been worn by every British queen, whether they reigned or were consorts, since the reign of King George IV.

The diadem was closely associated with Queen Elizabeth, who wore it on the way to her crowning ceremony in 1953 and en route to most State Openings of Parliament. King Charles’ mother was also pictured in it across British and Commonwealth coinage, banknotes and stamps. It is distinct for its design of four crosses alternating with four sprays representing the national emblems of England (roses), Ireland (shamrocks) and Scotland (thistles).

Queen Camilla further accessorized her most regal birthday look yet with a dangling pair of diamond earrings and Queen Elizabeth’s Coronation necklace, along with a silver clutch and matching shoes.

King Charles also looked the part at the State Opening of Parliament on July 17, where he arrived in his uniform of Admiral of the Fleet Royal Naval Number 1 Dress with cap and sword before changing into the Parliament Robe of State and the Imperial State Crown. The key ceremony marked his third time wearing the regal headpiece, having sported it for the first time at his coronation in May 2023 and again at the parliamentary kickoff that November.

Though the King, 75, was crowned with the nearly 5-lb. St. Edward’s Crown at Westminster Abbey in 2023, used only to crown a new king or queen during the coronation, he switched it for the lighter Imperial State Crown toward the end of the service. King Charles also appeared in it on the Buckingham Palace balcony and in official portraits from the historic day.

The latest State Opening of Parliament was highlighted by the sovereign’s delivery of the King’s Speech, composed by the government to outline its policies and proposed legislation for the new parliamentary session.

It’s been a busy week for the royal couple, who spent July 15 and 16 in the Channel Islands of Jersey and Guernsey off the northwest coast of France to highlight the special and historic relationship between the Crown Dependencies and the royal family, which traces back centuries.

In late April, Buckingham Palace announced that the King was resuming public-facing duties while continuing treatment for cancer. The palace announced the diagnosis in early February.