The recent announcement of Price William's engagement to Kate Middleton is certain to see a huge boom in the Royal memorabilia market.
Collectors will be eager to invest in items commemorating the wedding, just as they were 30 years ago when his parents Charles and Diana were married at St Pauls Cathedral. Their ceremony was watched by hundreds of millions worldwide, and if the global reaction to the latest announcement is anything to go by next year's Royal wedding should be equally as popular.
The royal memorabilia market has always seen reliably solid returns for collectors and investors alike, with the value of Diana's signature (such as this superb example) increasing by an amazing 580% over the last ten years (according to the industry's PFC40 index).
With less than a year to go before the next big day it seems the interest and speculation surrounding the event is set to grow and grow, meaning it could be the perfect time to invest in some royal collectibles.
Here we've compiled 6 of the most expensive and unique royal collectibles from recent years.
1) In 1987 the Duchess of Windsor's jewellery broke the record for such a collection when it was sold by Sotheby's for a combined £31m, a record that still stands to this day. The star of the auction was Wallis Simpson's engagement ring, the fabled Mclean diamond, which sold for an amazing £1.8m to a Japanese collector.
Amongst the other notable sales was a plume-shaped diamond brooch bought via the first ever auction video-link by Elizabeth Taylor for £400,000 (allegedly outbidding a dealer working for Prince Charles).
2) There may be a great deal of money in royal romances, but it also seems to be true of a royal divorce. Henry VIII was the most notorious of royal divorcees, and a letter handwritten by him to the Pope in an attempt to annul his marriage to Catherine of Aragon is certainly amongst the most unique pieces of royal memorabilia ever to come onto the market.
This amazing historical document paved way for the creation of the Anglican Church, and is currently available for £275,000.
3) The black taffeta gown worn by Diana in 1981 on her first public appearance as Prince Charles's fiancé sold this year for £192,000, smashing its original estimate. The dress, designed by Elizabeth and David Emanuel, was bought by Chilean fashion museum Fundación Museo De La Moda, along with the original copy of the invoice, design sketches and photographs of Diana wearing it.
The backless dress was seen by many as too daring, but it helped turn the 19-year-old Diana into an overnight fashion icon and launched her into the public eye in amazing style.
4) Earlier this year a Jaguar used by the Queen to drive herself around the Windsor Estates sold at auction for $77,000. It had been specially built for her and contained several modifications, including a tray in the arm-rest purpose built to hold her handbag and covers for the magazine holders in the doors to prevent her Corgis sliding into them.
It had previously contained a direct secure telephone link to Downing Street and the Home Office, but this was (perhaps wisely) removed before the car was sold to a Japanese collector.
5) A series of letters from Princess Diana to her former nanny sold at auction in 2008 for £27,000. The letters gave a poignant insight into her life and marriage, including the admission that "watching me dance is like watching an elephant."
In the letters, written between 1978 and 1983, she also spoke of her upcoming marriage, her relationship with the Royal family and her subsequent loneliness within the spotlight of public life.
6) A series of intimate love letters written by Prince Charles to British Consulate receptionist Janet Jenkins were sold on eBay in 2009 to an anonymous bidder for £20,744. One of the notes was written in 1980, a year before his marriage to Diana, with the others dating from 1976.
In the letters Charles spoke of his frustration at being in the public eye, and his fear of marrying the wrong woman. In one he noted "I shall just have to get married as soon as possible and then all these people will relax a little. I still think my solution of marrying a girl from each Commonwealth country is the best one."
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