This week's diplomatic reception at Buckingham Palace had a dress code of white tie, and the Duchess of Cambridge was suitably dressed for the occasion in a festive velvet Alexander McQueen gown - paired with some sparkling accessories.
Her most notable accessory was the Lover's Knot Tiara, which Kate has worn on several occasions. Originally designed by the House of Garrard for Queen Mary in 1913, the regal headpiece features both diamonds and pearls and was a favourite piece of Kate's late mother-in-law, Princess Diana.
The neckline of Kate's navy velvet gown also perfectly showed off the striking diamonds on the Nizam of Hyderabad necklace, which was given to Queen Elizabeth on her wedding day. She chose statement earrings to match, and of course sported her honours: the pale yellow Royal Family Order and the sash and brooch indicating the Royal Victorian Order, which Kate received from Queen Elizabeth earlier this year on the anniversary of her wedding to Prince William.
The duchess' iconic sapphire and diamond engagement ring was also recognisable on her left hand. But one of her other accessories wasn't so easy to identify.
As pointed out by royal blogger What Kate Wore, pictures taken inside the event appear to show the royal wearing a new ring on her right hand. Most photos were taken from a distance, so it's difficult to make out the exact design, but the reception is thought to be the first time Kate has worn this piece.
It's also unclear at this point if it is a wholly new design, something from the royal collection, or perhaps existing stones fashioned into something bespoke for Kate.
While Buckingham Palace did confirm some details of her outfit, they did not mention the ring, so its provenance will remain a mystery for now...
You Might Also Like