Only 12 men have ever walked on the moon. Anything associated with them and their space missions is likely to be valuable and few things more so than things they used or wore during their moonwalks.

We've already covered some of the items to be offered in Heritage's Space Sale, specifically a cheque with Neil Armstrong's signature and a silver Robbins medallion flown on Apollo 11.

Even rarer, however, is a nametag from one of the 12: Apollo 14's Lunar Module Pilot Dr Edgar Mitchell.

There are, as you'd expect, only 12 nametags from suits which have been walked on the moon. The first two: Neil Armstrong's and Buzz Aldrin's, are in the Smithsonian Museum, whilst Apollo 12's Alan Bean reduced his to fragments for use in his famous paintings.

So Mitchell's nametag is one of only nine which are ever likely to appear at auction. Usually the tags which have been put up for sale have been offered as part of a set of four: the name tag, a NASA logo patch, an American flag, and the mission insignia patch.

Nametag of Apollo 14's Moonwalker Edgar Mitchell

"The prices for these sets have reached $350,000 more than once," said Michael Riley, Senior Cataloguer and Chief Historian at Heritage Auctions.

"It's been a number of years since any other lunar surface-worn name tag has been offered to the public and it will likely be many more years before another becomes available. Clearly, this would be the centrepiece for any serious space collection."

The reverse of the nametag, with Mitchell's signature

Apollo 14, following on from the hair-raising near-tragedy of Apollo 13, was the third moonlanding. Mitchell (and his name tag) and Commander Alan B Shepard spent nine hours and twenty-two minutes exploring the lunar surface and doing experiments. Shepard even had time to play golf.

Included with the lot is a signed, illustrated Letter of Certification from Dr. Mitchell dated February 22, 2008. It reads as follows:

"This is to certify that the accompanying - Apollo Spacesuit Name Tag - imprinted with the name 'MITCHELL' and inscribed by me on its verso as 'Worn on the Moon', is the actual Apollo spacesuit name tag worn by me on the Moon during February 5th and 6th, 1971."

Mitchell goes on to mention that the badge's smudges are almost certain to be moon dust. The piece is estimated at $75,000.

Heritage's space sale takes place on Wednesday April 21 in Dallas, with online bidding available until the day before.

Space collectors may be interested to know that a photo signed by a member of each Apollo lunar-landing mission including Mitchell is available for sale right now, as is a signed training suit of Buzz Aldrin's and some of Neil Armstrong's hair.

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