Diamonds are no laughing matter in the royal family, in fact there is even a special rule attached to them, which states they shouldn't be worn before 6pm, and there's a host of other protocols to follow when it comes to wedding day tiaras too.
So it doesn't come as a surprise that their maintenance is taken very seriously, as it just wouldn't do if the diamonds didn't sparkle at all times.
However, the Queen's special cleaning hack may come as a surprise, as it's one you can even try at home yourself.
According to Angela Kelly, the Queen's dresser and author of The Other Side of the Coin: The Queen, the Dresser and the Wardrobe, all that's needed is a bit of gin and water, as revealed in HELLO! and in her book.
And that's not the only cleaning hack she uses. Apparently a spot of washing up liquid is ideal to remove hair spray stains that could tarnish jewellery.
In her book, Angela also reveals the Queen loves a good bargain, and she tries to keep costs down where she can. So much so that on a trip to Singapore, Kelly picked up some silk in a bargain bucket and almost missed the royal flight as she'd been told she could claim tax back on them at the airport, making it just in time for take off.
'The look on the Queen's face was priceless as I handed her the tax refund,' she writes.
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Penny Goldstone is the Digital Fashion Editor at Marie Claire, covering everything from catwalk trends to royal fashion and the latest high street and Instagram must-haves.
Penny grew up in France and studied languages and law at the Sorbonne Nouvelle University in Paris before moving to the UK for her MA in multimedia journalism at Bournemouth University. She moved to the UK permanently and has never looked back (though she does go back regularly to stock up on cheese and wine).
Although she's always loved fashion - she used to create scrapbooks of her favourite trends and looks, including Sienna Miller and Kate Moss' boho phase - her first job was at MoneySavingExpert.com, sourcing the best deals for everything from restaurants to designer sales.
However she quit after two years to follow her true passion, fashion journalism, and after many years of internships and freelance stints at magazines including Red, Cosmopolitan, Stylist and Good Housekeeping, landed her dream job as the Digital Fashion Editor at Marie Claire UK.
Her favourite part of the job is discovering new brands and meeting designers, and travelling the world to attend events and fashion shows. Seeing her first Chanel runway IRL at Paris Fashion Week was a true pinch-me moment.
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