The story behind the Duchess of Cambridge's state banquet diamonds and pearls, loved by Princess Diana and the Queen Mother

A state banquet is always an excuse to dust off extravagant jewels, and last night the Duchess of Cambridge wore several generations’ worth of royal jewellery at once, pairing the 1913 Cambridge Lover’s Knot tiara with pearl earrings believed to have belonged to Princess Diana, and a pearl and diamond necklace made for Queen Alexandra in 1863.

The Lover’s Knot tiara is becoming the Duchess’ go-to for white-tie events: she wore it to a reception at Buckingham Palace in 2015 and again in 2016, to a state dinner for the King and Queen of Spain last July, and to a Christmas party hosted by the Queen in December.

Last night she wore it with a pale blue Alexander McQueen gown made from taffeta fabric - a material that has for over a decade been considered, well, naff, but that has made an unexpected comeback just in time for party season. Teamed with the tiara, the sculpted taffeta gown has an Eighties Sloane Ranger feel to it, offering yet another nod to Diana's timeless style.  

The Cambridge Lover's Knot tiara was made by Garrard for Queen Mary, the Queen’s grandmother. It features 19 baroque pearl pendants suspended beneath diamond bow motifs and was made using diamonds and pearls taken from other pieces of jewellery she owned.

The Queen inherited the tiara in 1953 and wore it several times early in her reign; she then lent it to Princess Diana, who, like Kate, wore it to state banquets - despite allegedly complaining that it was so heavy it gave her headaches.

Diana memorably wore the tiara to a white-tie event in Hong Kong with a high-collared Catherine Walker jacket, an outfit that earned itself the nickname ‘the Elvis look’.

On more than one occasion, Princess Diana wore the Lover’s Knot tiara with the elegant Collingwood pearl drop earrings that the Duchess of Cambridge wore at the reception for King Willem-Alexander and Queen Maxima of the Netherlands.

The Duchess took the pearl-and-diamond theme one step further by wearing Queen Alexandra’s historic necklace, which hadn’t been worn in public for over 25 years.

Featuring eight pearls surrounded by diamond festoons, and a further three detachable diamond and pearl drop pendants, the necklace was part of a parure of jewellery bought by the future King Edward VII for his bride.

The parure also included a tiara, earrings and a brooch; Alexandra wore everything except the tiara on the wedding day itself. The jewels passed from Queen Alexandra to her daughter-in-law, Queen Mary, who later gave the necklace to her own daughter-in-law, the Queen Mother.

The Queen Mother wore the necklace frequently, including to the last UK state banquet honoring the Netherlands in 1982 - so it could be that the Duchess of Cambridge is following that tradition.

When the Queen Mother died in 2002, the necklace became part of the Queen’s collection, re-joining the earrings and brooch which the Queen had inherited in 1953.

The rest of the royal family showcased equally dazzling jewels. The Queen herself wore the Girls of Great Britain and Ireland tiara, another Garrard piece that was commissioned as a wedding gift for Queen Mary in 1893. The tiara originally featured pearls that were removed to be used in the Lover’s Knot tiara worn by the Duchess of Cambridge.

The Duchess of Cornwall, meanwhile, wore her own go-to tiara: the Greville tiara, made by Boucheron in 1921 for the Hon. Mrs Margaret Greville - the socialite who bequeathed her vast collection of jewels to the Queen Mother, including the emerald and diamond tiara worn by Princess Eugenie on her wedding day.

Like the Duchess of Cambridge’s pearl and diamond necklace, the Greville tiara was a favourite of the Queen Mother, and she was pictured wearing both of them together. So while the dinner honoured the visiting Dutch monarch, the jewellery worn paid tribute to absent family members in a way that only the royals can.

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