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But Superman's first appearance was not the well-known comic in the collection. A fine copy of the first appearance of Batman in Detective Comics no. 27 sold for $522,000. The first appearance of the Human Torch in Marvel Comics no. 1 netted $113,525.

The prices for these three comics--all on the short list of the half-dozen most important comics ever--were about average for similar sales of late.

Record prices were paid for the most pristine copy of Captain America no. 2 (CGC grade 9.4) on record and a very fine copy of the rare All-American Comics no. 16. Captain America sold for $113,525 and All-American for $203,150.

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In total the 222 comics from the Golden Age of the '30s and '40s brought in $3,433,342, exceeding the initial estimate of $2 million. About 100 more lesser-known books expected to sell for around $100,000 will be auctioned off online.

Rarely does a collection of this breadth and quality appear out of nowhere. Michael Rorer discovered the comics in a closet in the home of his recently deceased great aunt in Martinsville, Virginia. They had belonged to his great uncle Billy Wright, who had bought most of them when he was 9-14 years old. Wright, a lifelong bachelor, preserved the books his whole life, and when he died in 1994, they were stored at his sister's house.

Rorer's great aunt had mentioned the comics to him a few times before her death but without giving any indication of their worth. He only had an inkling of their value when he casually mentioned what he found to a co-worker who said it would be neat if the collection included Action Comics no. 1. When Rorer saw the first Superman in the collection, he started assessing its value.

Comic experts were shocked when they learned about the collection. "This is just one of those collections that all the guys in the business think don't exist anymore," said Lon Allen, an executive at Heritage Auctions, which handled the sale. J.C. Vaughn, who works at Overstreet which publishes the standard comic price guide, said, "The scope of this collection is, from a historian's perspective, dizzying."