Angela Kelly, the Queen's style advisor and dressmaker, shares unusual cleaning tips in her new book

When Queen Elizabeth's longtime dressmaker needs to clean the monarch's priceless jewels — she reaches for something quite unexpected: a bottle of gin!

The surprising revelation is one of many in Angela Kelly's book The Other Side of the Coin: The Queen, The Dresser and the Wardrobe. "A little gin and water come in handy to give the diamonds extra sparkle — just don't tell the jeweler!" writes Kelly.

Discussing the preparations in getting the Queen ready for formal events like the State of Opening of Parliament, which includes laying out her precious jewels and her diadem on a tray that once belonged to the Queen Mary, Kelly adds: "A drop of washing-up liquid and water will get rid of any hairspray stains."

It's yet another insider detail revealed in the book, written by Kelly with the Queen's approval. Having worked for Her Majesty since 1994, Kelly, whose official title is Personal Advisor and Curator (The Queen's Jewellery, Insignias and Wardrobe) and In-House Designer, is responsible for the care of the Queen's clothing and jewelry as well as creating some of the monarchs most iconic looks.

Christmas Day church service, Sandringham, Norfolk, UK - 25 Dec 2018
Queen Elizabeth
| Credit: Tim Rooke/REX/Shutterstock

Of course, the Queen's priceless jewels are professionally cleaned when needed. "The Queen's jeweller will give the stones a deep clean when necessary, so for me it's just a matter of a quick polish and they're sparkling once more."

Vladimir Tiara
Queen Elizabeth
| Credit: Mark Cuthbert/UK Press via Getty

In addition to gin, Kelly, who was born in Liverpool, also revealed that she used a tea bag to dye the replica royal christening gown by dunking each piece of lace in a small bowl filled with cool water and Yorkshire tea.

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Last month, the Queen (and presumably Kelly) made the decision not to wear the historic and heavy Imperial State Crown to the opening of Parliament, instead opting to wear the much lighter George IV State Diadem. The purple velvet bejeweled crown (complete with 2,868 diamonds) was instead placed on a red cushion to the side of the Queen's throne.