It’s a big week for Princess Kate.
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On Tuesday, she will attend her very first state banquet as the Princess of Wales – and royal fans are eagerly anticipating what she will choose to wear.
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Royal ladies are permitted to wear tiaras on the occasion of state visits and Kate is therefore expected to don a glittering headpiece in honour of the President of South Africa this week.
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It is not known which tiara Kate will wear to the grand event – but there is one significant piece of jewellery she definitely won't be wearing.
Princess Diana pictured wearing the Spencer Tiara
While it would have been fitting for her to showcase the tiara worn by her late mother-in-law Princess Diana – the former Princess of Wales – on her wedding day, she is unable to for a very simple reason.
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Diana wore the Spencer tiara for her marriage to the then-Prince Charles in 1981. The glittering headpiece is designed in a garland style and features a central heart flanked by continuous running scrolls, interspersed with star and trumpet-shaped flowers.
She wore the glittering headpiece on her wedding day
It is set throughout with circular and rose-cut, cushion, and pear-shaped diamonds, mounted in gold.
However, following Princess Diana's untimely death in 1997, it reverted back to the Spencer family and therefore remains in their care.
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To date, Princess Kate has only worn three tiaras in total.
Princess Kate showcased the Cartier Halo tiara for her nuptials
The first time we saw her wearing a tiara was on her wedding day to Prince William in 2011. For the highly anticipated event, watched by millions, she wore the Cartier Halo design, which perfectly complemented her Alexander McQueen wedding dress.
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Traditionally, tiaras are a symbol of marriage and are often donned by brides on their special day.
The royal pictured wearing the Lotus Flower Tiara
Princess Kate has also been photographed wearing the dazzling Lotus Flower Tiara – one of Princess Margaret's favourite designs, boasting pearls and diamonds.
And finally, the royal has chosen to pay tribute to her late mother-in-law in the past by showcasing Diana's most worn tiara – The Lover's Knot.
Princess Diana favoured the Lover's Knot Tiara
Princess Kate has worn the tiara on eight separate occasions – and perhaps she will do so again on Tuesday night!