Kate opted for the same necklace and earring combination that she wore just over a year ago for the Duke of Edinburgh’s funeral.
The pieces of jewellery were also previously worn by her husband’s late mother, Diana, and are thought to have been loaned to Kate for the first time by the Queen in 2017.
Described as a Japanese choker with four rows of pearls and a curved central diamond clasp, this was accompanied with a pair of Bahrain drop pearl earrings.
The Queen was pictured wearing the set during an engagement in Bangladesh in 1983, having loaned the set a year earlier to Diana to wear during a state visit from Queen Beatrix of the Netherlands.
Kate was also seen wearing the necklace to the Queen and the Duke of Edinburgh’s 70th wedding anniversary dinner in 2017.
The necklace is said to have been commissioned by the Queen using pearls which were a gift from the Japanese government after her first state visit to the nation in 1975.
The earrings were made using two from a collection of pearls given to the Queen as a wedding gift from the Hakim in Bahrain in 1947.
By contrast, the Duchess of Sussex opted for pared back jewellery with a pair of pearl and diamond stud earrings which were given to her by the Queen as a gift when she joined the Royal Family.
Meghan wore the earrings on her first joint engagement alongside the Queen in June 2018, when they marked the opening of a new bridge in Cheshire.
Pearls are often referred to as mourning jewellery, a tradition said to date back to Queen Victoria’s era.
Camilla, the Queen Consort, wore Queen Victoria’s Hesse Diamond Jubilee Brooch – diamonds in the shape of an open heart, with two sapphire pendants.
This was accompanied by a pair of oval stud earrings featuring a sapphire stone encircled with diamonds and a gold pendant necklace.
In a nod to the Queen’s lifelong love of horses, Princess Charlotte wore a small diamond horseshoe brooch which was a gift from her late great-grandmother.