Kate Middleton was described as a "head-turner" during the 2019 Diplomatic Corps Reception at the Buckingham Palace. Although she looked stunning, as always, in every public engagement, her overall style and appearance were much more remarkable in the eyes of the royal fans and supporters.

According to Express UK, the Duchess of Cambridge wore an Alexander McQueen black velvet dress. The dress alone was already iconic as per sources. But, her accessories and pieces of jewelry complemented further her look for the night.

It was noted that she wore her "go-to" piece, the Lover's Knot tiara, which was once a favorite piece of the late Princess Diana. Along with her tiara, she wore matching pieces for her neck and ears.

As seen in the photos and clips, Kate Middleton wore the Nizam of Hyderabad necklace, and a pair of earrings from the iconic Diamond Chandelier Drop Demi-Parure set.

The publication revealed that the necklace was lent to the duchess by Queen Elizabeth II. As it follows, this was a wedding gift for the Queen in 1947 when she married Prince Philip.

The Duchess of Cambridge also wore her iconic sapphire engagement ring, which was once owned by the Princess of Wales. While Kate is known to always wear this ring given to her by Prince William, royal fans and supporters were surprised to see another ring worn by the duchess. As reported by Harper's Bazaar, the diamond ring on her right ring finger was "unrecognizable." It was new to the eyes of everyone, a source added.

Up until today, the origins of the notable diamond ring remain unknown. Some reports have been speculating that it might be a gift from a Middle Eastern ruler for the Queen, which was only lent to Kate Middleton.

Others, however, believe that the ring is possibly a gift from Prince William. Regardless, the stunning diamond ring seemingly completed the Duchess of Cambridge's appearance for the event.

Aside from the gown and accessories, Kate Middleton was also seen wearing her Royal Victorian Order royal blue sash and Royal Family Order brooch. Unlike her pieces of jewelry, these accessories were said to possess more value for the royal family. The reason being is that the sash and brooch "signify" the titles that were passed on to Kate Middleton by Queen Elizabeth II.

It was revealed that the sash signifies her title as Dame Grand Cross of the Royal Victorian Order. As for the brooch, it is more of a personal memento, rather than a state decoration, a source explained.