Every time Kate, Princess of Wales has worn Bahraini pearl earrings to public engagements

The pearls were originally a wedding gift for Queen Elizabeth II and Prince Philip in 1947

Kate, Princess of Wales, left, wearing Queen Elizabeth II's Bahraini pearl earrings. She first wore them in public while attending the Remembrance Sunday ceremony with Camilla, Queen Consort in November 2016. AFP

The following year, she borrowed the earrings to attend Royal Ascot in June. Reuters

In August 2018 she wore the earrings to attend church with Queen Elizabeth. Photo: Invicta Kent Media / Shutterstock

Camilla, left, and Kate, who is wearing the pearl earrings, take part in the Trooping the Colour in June 2019. Reuters

The queen and Kate attend the Remembrance Sunday ceremony in London in 2019. AFP

Pearls are worn as part of royal mourning fashion protocol. Kate borrowed the queen's pearl earrings for the funeral of Prince Philip in April last year. Reuters

Kate wore them in June to attend the National Service of Thanksgiving held at St Paul's Cathedral during the queen's platinum jubilee celebrations. Reuters

Kate also wore the earrings for the funeral of Queen Elizabeth. Reuters

Kate wore the earrings on Saturday to attend the Festival of Remembrance with William, Prince of Wales. AFP

The Princess of Wales is known for making considered style choices, honouring people and places through her sartorial choices. The Festival of Remembrance on Saturday was no exception.

The British royal chose to wear the Bahrain Pearl and Diamond Drop Earrings, which are made with two Bahraini pearls and were loaned to her by Queen Elizabeth II in the past.

The festival is dedicated to all those who have "served and sacrificed from Britain and the Commonwealth". This year, the memory of the queen was also celebrated.

The earrings the princess chose to wear each feature one brilliant-cut round diamond, four small round diamonds and three baguette-cut diamonds, with the Bahraini pearl dangling below. The pearls are from a selection of seven given to Queen Elizabeth and Prince Philip in a shell for their wedding in 1947 by Sheikh Salman bin Hamad Al Khalifa of Bahrain.

Significantly, Kate wore the earrings to both the queen's funeral in September and to Prince Philip's in April last year. For the festival, she also chose to wear the same four-row Japanese pearl choker necklace, also from the royal collection, that she wore to both funerals.

She has worn the earrings on a several occasions since 2016, when she was first lent them by the queen to wear on Remembrance Sunday. The year before, the queen wore the pieces to attend the Festival of Remembrance.

In the years since, the Princess of Wales, then Duchess of Cambridge, has worn the earrings to attend Royal Ascot in 2017, to church in Balmoral in the summer of 2018 and for the 2019 Trooping the Colour.

Aside from periods of mourning and funerals, Remembrance Sunday is the only time British royals typically will wear black outfits. As pearls are worn as mourning jewellery in British royal custom, she wore them in later in 2019 on Remembrance Sunday.

The practice of wearing pearls as mourning jewellery dates back to Queen Victoria, who only wore pearl and black jewellery after the death of her husband, Prince Albert, in 1861.