The handwriting of the great and the good, and especially their signatures, has been valued highly for millennia - the Great Library of Alexandria being one of the earliest and greatest examples of this.
Of course, just because you want an autograph doesn't mean that there is one around for you to buy (or beg/borrow/steal). Sometimes few autographs survive the years - perhaps the signer died young or just weren't held in high regard during their lifetimes. With that in mind, here are our top five elusive autographs:
The first man to set foot on the moon has an awkward relationship with the inevitable celebrity which followed, finding the interest in himself and memorabilia related to him relentless. He even tried to sue his barber on discovering that the latter had been selling his hair clippings.
Whilst he is typically polite in his refusals to sign autographs he makes no exceptions, famously refusing to sign for US Speaker of the House Nancy Pelosi in 2009.
Whilst the total number of Armstrong's signatures in existence is not particularly low, they are increasingly scarce compared to the unchecked demand, causing the value to leap up by an extraordinary 900% from 2000 to 2010 according the PFC40 index. A flight plan bearing his famous 'small step for man...' quote and signature sold for $152,000 last year.
J D Salinger
If it's perhaps a slight exaggeration to say that Armstrong is reclusive, this can hardly be denied for J D Salinger, author of the world famous The Catcher in the Rye (and a handful of other works, such as Franny and Zooey).
Salinger gradually withdrew from public life during the early 1950s and became extremely reluctant to be photographed or interviewed. He refused to reply to letters from his fans and his autograph became extremely scarce for collectors.
When Nicholas Cage proposed to Patricia Arquette she hesitated, and he suggested that she set him a quest of some kind to prove his love. She listed three 'impossible' requests: a wedding dress from an elusive Tibetan Tribe, a black orchid and a J D Salinger autograph.
(Cage did return with these items - though he had to spray-paint the orchid.)
As Salinger died last year, no more autographs will be forthcoming. So whilst there are a few around (we sold one ourselves) there are not nearly enough for Salinger's fans - after all The Catcher in the Rye continues to sell hundreds of thousands of copies a year.
The signing of the US Declaration of Independence was one of the most momentous events in American history. So it should be no surprise to hear that attempting to gather up an example of every signer's autograph is a popular goal in America.
It's some task, however. None of the 56 signatures are common or cheap, but the most difficult might surprise those not in the know, as it's not Thomas Jefferson, Benjamin Franklin or even John Hancock but Button Gwinnett.
Gwinnett voted in favor of the Declaration of Independence on July 4, 1776, and signed the famous parchment copy on August 2, 1776.
He did not have long to live however. He became Governor of Georgia for just two months in 1777 before dying in a duel with bitter rival Lachlan McIntosh. A document he signed on July 12, 1776 from the James Copley collection sold for $722,500 last year.
William Shakespeare's plays are performed and celebrated around the world, and he is universally regarded as a genius.
All great writers naturally have valuable autographs, but in Shakespeare's case just six are known and all are held in institutions.
It is difficult to be sure how much one would sell for if it came to auction now, but our experts typically put the value at several million dollars.
Gaius Julius Caesar was Rome's first emperor in all but name, and in extending its reach and centralising power he influenced the course of Western history for many years to come. (Fittingly, he was one of the subjects of Shakespeare's plays.)
So far as anyone has ever discovered none of his autographs has survived. But we know that they were once collected, as Pliny the Elder collected autographs and bemoaned the fact that those of Caesar were becoming difficult to find.
It's a useful reminder of how cherished collectibles become scarcer and only survive with the dedication of collectors and museums.
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