The late Queen Elizabeth II's personal jewellery collection includes some of the rarest jewels in the world, but arguably the most impressive in the royal archive is the Nizam of Hyderabad necklace – estimated to be worth around £66.3 million.
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The necklace was a present for the Queen – then Princess Elizabeth – to honour her wedding day to Prince Philip in 1947. The Nizam of Hyderabad, the monarch of India's Hyderabad State, Asaf Jah VII, invited the royal to choose two pieces of jewellery from Cartier for her wedding gift.
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She opted for a dazzling tiara and breathtaking necklace based on the petals of an English rose – which is now deemed one of the most expensive pieces of jewellery in the royal collection.
The Princess of Wales was lucky enough to wear the Queen's incredibly sentimental jewels when she attended a black-tie reception at the National Portrait Gallery in 2014. Wearing a midnight-blue Jenny Packham dress for the occasion, Princess Kate embellished her outfit with the multi-million-pound platinum and diamond necklace personally lent to her by the Queen.
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The Princess wore the Queen's necklace in 2014
The Princess of Wales remains the only royal lady to have worn the Nizam of Hyderabad piece besides Queen Elizabeth. In light of the monarch's death, it seems likely the necklace's new ownership falls to Kate, who may be in line to inherit the precious piece.
Cartier originally crafted the necklace in the 1930s. Its breathtaking centre piece is pave-set with a detachable double-drop pendant, 13 emerald-cut diamonds and a pear-shaped drop.
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The piece is worth an estimated £66.3 million
The original version, which was purchased in 1936 but bought back by Cartier a year later, had three triple-drop and eight double-drop pendants.
The Nizam of Hyderabad necklace isn't the only piece of jewellery the late Queen personally lent to her grandaughter-in-law. One of the rarest pieces in the Crown Jewels collection of 23,578 gemstones is the George IV State Diadem, officially known as the Diamond Diadem.
The late monarch was gifted the Nizam of Hyderabad necklace for her wedding
It's estimated to be worth nearly £800,000 today and is one of the most symbolic crowns in the royal collection. It's particularly special because it's strictly reserved for sovereigns and Queen Consorts.
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When Prince William eventually becomes King, his wife will inherit Camilla's title of Queen Consort. The Princess of Wales will then share the privilege of wearing the prized jewels.
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