The royal family this week vetoed 18 dental X-rays featuring Elizabeth II and those of her mother and father, King George VI, from going to auction, much to the disappointment of royal memorabilia investors.

The 18 images, found in a house in Surrey, were taken between 1942 and 1946 and had been due to appear this Wednesday at Dominic Winter's auction house.

Not to be deterred, here is our guide to the top five collectible X-rays.

Marilyn Monroe's chest

In June 2010 an X-ray of Marilyn Monroe's chest brought 20 times more than its estimate at a Julien's Auctions event, achieving £15,400.

The X-rays were taken at the Cedars of Lebanon Hospital in Florida in November 1954, where Monroe had surgery for endometriosis.

Marilyn's chest continues to fascinate

Albert Einstein's skull

A pair of X-rays of Einstein's skull taken in 1945 realised £24,000 in 2010, 20 times its estimate. The images were taken 10 years before the theoretical physicist died at the age of 76.

They were captured by Dr Gustav Bucky, a forerunner in radiograph technology who collaborated with Einstein on the invention of the Automatic Electric Eye camera in 1937.

John F Kennedy's pelvis

Taken in 1947 after the future president collapsed in London, suffering from Addison's disease, five X-rays of JFK's pelvis made £17,430 in October 2010.

First X-Ray of the human body

The first X-ray of the human body was taken by German Wilhelm Conrad Röntgen of his wife's hand in 1895. Röntgen had discovered the secret to X-rays a week earlier, while experimenting with his cathode ray generator. Were this item ever come to auction we would expect it to achieve a substantial sum.

First X-rays taken in Britain

A collection of seven of the first X-ray photographs created in Britain, by Alan Archibald Campbell Swinton, went to auction with a low end estimate of £10,000 in March 2011 but failed to sell. The images were taken just weeks after Röntgen's discovery and are sure to appear on the market again soon.