Superman and Batman's first appearances in comic books have each set auction sales records and broken the $1 million barrier, in an age when traditional investments have fared badly and superheroes look attractive.
Three days earlier, a buyer paid $1 million for Superman's world debut in Action Comics #1, more than tripling the previous comic book sales record set last year.
Shirrel Rhoades, former publisher and executive vice president of Marvel Comics, said high sales for those comics is partly a reflection on the poor economy.
"When the stock market is down, when real estate investments are over the cliff, collectibles offer an alternative that you can invest in that may have some growth potential," Rhoades said.
He said the 1938 Action Comics #1 is arguably more historic than the first appearance of Batman, but that this week's sales seem to be following their own logic.
"We're probably seeing a little bit of a feeding frenzy," Rhoades said. "With the sale of Action #1 for a million, I think that's going to keep prices up for awhile."
Heritage Auction Galleries did not disclose the name of the previous owner or the winning bidder for Detective Comics #27, the first book featuring Batman.
The previous owner is a savvy collector who bought the comic for $100 more than 40 years ago, a figure which at the time seemed a large price, said Heritage Auction Galleries.
ECONOMY DOWN, COMICS UP
The Action Comics #1 sale was handled by ComicConnect.com, and Vincent Zurzolo, chief operating officer of the website, echoed Rhoades' view that comics are fetching record sums because they are an attractive investment in a down economy.
He said buyers pay high sums for vintage comics because they want something "they're familiar with, that they feel comfortable with, that they think are good investments."
Back in the 1930s, both Action Comics #1 and Detective Comics #27 sold for 10 cents.
Experts said the same edition of a comic can vary widely in price, depending on condition.
Heritage Auction and CommicConnect said the books they sold this week were pristine, well-preserved copies.
Rhoades said he owns a ragged copy of Action Comics #1 that lacks a front cover and is worth very little.
But he said that more than eight years ago, he gave an art college a 1963 Amazing Spider-Man #1 then worth $40,000. He estimates the figure has since climbed above $100,000.
"My wife jokingly said why did I give it away, when I could have kept it and sold it a few years later for more than double its value," Rhoades said.