In their revelatory interview with Oprah, the Duke and Duchess of Sussex were at pains to single out one member of the royal family for wholeheartedly welcoming Meghan into the fold: the Queen. “She’s always been warm and inviting,” the Duchess said of Prince Harry’s grandmother.

Concrete proof of Her Majesty’s stamp of approval? The “beautiful pearl earrings and matching necklace” that the Queen gave Meghan during their first joint engagement together, a train trip to Cheshire, in June 2018 for the official opening of the new Mersey Gateway Bridge.

The Duchess wore the diamond and pearl earrings with her Givenchy Haute Couture dress for the occasion, together with a diamond tennis bracelet. Buckingham Palace didn’t release any other information about the earrings, such as whether they were newly purchased or a vintage piece from the Queen’s collection, and to this writer’s knowledge the Duchess has never been photographed wearing the matching pearl necklace in public.

It’s not the first time the Queen used pearls to welcome a new member of the royal family. Shortly before Lady Diana wed Prince Charles in 1981, the Queen presented her with the Lover’s Knot tiara, which would go on to become the piece the pearl-loving Princess wore for most state events. Made by Garrard in 1913 for Queen Mary, the Queen’s grandmother, the diamond tiara features 19 baroque pearl pendants.

After Diana’s death, the tiara was returned to the Queen’s collection, and wasn’t seen in public until the Duchess of Cambridge began wearing it to state events in 2015.

The Duchess of Cambridge was also welcomed into The Firm with a pair of diamond and pearl earrings that the Queen wore for her Silver Jubilee celebrations in 1977. She has regularly borrowed the Queen’s Bahrain pearl and diamond drop earrings, created using two of the seven pearls that the Queen received as a wedding gift from the ruler of Bahrain in 1947. She has also been pictured wearing a four-strand pearl and diamond necklace that Diana, too, borrowed from the Queen.

The Queen herself, like generations of female monarchs before her, is rarely seen without at least one strand of pearls around her neck. She has several strands that form part of her uniform for official engagements.

Two strands were wedding gifts from her mother and father; one had belonged to the last Stuart monarch, Queen Anne, while the other belonged to Queen Caroline, and she wore them together on her wedding day.

The Queen’s go-to everyday style is a three-strand pearl necklace, and she reportedly rotates three near-identical pieces, one of which was a gift from her grandfather, George V, for his Silver Jubilee in 1935, when she was nine.

But the Queen’s pearl necklace collection began even earlier. She was photographed aged three wearing a platinum chain adorned with six pearls: her father would add two more each birthday, continuing a tradition started by her great-great-grandmother, Queen Victoria.

A symbol of purity and integrity, the link between queens and pearls dates back thousands of years. It’s almost impossible to find an official portrait of a queen that doesn’t feature pearls: whether swaggering ropes, tightly bound chokers or classic strands. One of the most important crowns in the royal collection, the diamond diadem made for King George IV’s coronation in 1821, features two rows of pearls.

Queen Elizabeth I famously used pearls to symbolise her chastity; the so-called ‘virgin queen’ was painted bedecked with the glowing white spheres all over her body and hair. In the 16th century, Europe became rich with treasures plundered by the conquistadors, including vast quantities of natural pearls.

Even the virgin queen’s collection couldn’t compare with that of the Queen of France, Catherine de’ Medici; who bequeathed one of her many ropes of pearls to her daughter-in-law, Mary Queen of Scots. In a twist of fate those floor-skimming pearls ended up around the neck of Queen Elizabeth after her cousin was beheaded, accused of plotting her assassination.

Centuries later, power pearls have an entirely new reputation. No longer the sole preserve of royalty and aristocracy, they’re one of the most democratic pieces of jewellery, worn by women of all ages, backgrounds and beliefs. In January this year, hundreds of thousands of women donned pearls - real or faux - in solidarity with the newly inaugurated Vice President of the USA, Kamala Harris, who has made pearls her signature accessory since her university days.

On the same evening that the Duchess of Sussex left the country open-mouthed with revelations of silencing and suicidal thoughts, her sister-in-law the Duchess of Cambridge sent a message of unity with the royal family in the Commonwealth Day broadcast. She, too, wore pearls: a pair of gold-vermeil £60 organic pearl hoops by Mejuri, a Canadian jewellery brand founded by a Jordanian woman.

Typical of the type of everyday jewels that women have bought for themselves in droves over the last year, the message behind them was one of democracy and accessibility. Which was another kind of power play altogether.

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