The holy grail of comic books is coming to eBay.
The internet auction site announced Wednesday that the finest known copy of Action Comics #1, the 1938 comic book that marks the first appearance of Superman, will be offered Aug. 14-24.
The book, which is being sold by collectibles dealer Darren Adams, received a 9.0 grade from the Certified Guaranty Company comic grading firm, according to a press release.
The only other copy of Action Comics #1 to receive such a high grade set a record when it sold for over $2 million in 2011, the eBay release said. The comic from the earlier sale "had cream to off-white pages, while the comic that will be available on eBay contains white pages and is in pristine condition," according to the announcement of August's auction.
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"This is an extraordinary opportunity to acquire the most valuable comic book in existence and we look forward to sharing a piece of pop culture history with the global eBay community of 149 million buyers," Gene Cook, general manager of Emerging Verticals for eBay Marketplaces, said in the release.
—By CNBC staff.