While fans are busy devouring J.K. Rowling and Jack Thorne's Harry Potter and the Cursed Child, they may want to check their bookshelves for the very first book in the series. A new report says a small error could fetch a lot of money at auction.

The Independent says a few first editions of Harry Potter and the Philosopher's Stone (known as the Sorcerer's Stone in the U.S.) that contain an error are very valuable. They write:

A first edition of Philosopher's Stone with a rare error - one of only 500 hardback copies in which “1 wand” is repeated twice in Harry’s list of Hogwarts school supplies - is expected to reach as much as £26,000 when it is sold at Bonhams Fine Books and Manuscripts Sale in London on 9 November. The passage with the typo appears in the editions on page 53.

That's around $33,588 at the current exchange rate. Bonhams’ Head of Books and Manuscripts Matthew Haley said, “As the first book in the series, Harry Potter and the Philosopher’s Stone has a special place in the affections of the millions of readers across the world and the proof reading error about the wand in the first edition has, of course, become a treasured piece of Harry Potter arcana.”

There's always many individuals in the editing process for books like this but that doesn't mean they're infallible. A fan posted about this particular error on Twitter a few years ago, though they say their copy is a paperback printed in 2000. But it does appear to be the same exact error. On a list of "Other Equipment" Hogwarts students will need in their first year "1 wand" is printed twice.

But if you think you might have one of the hard cover versions (they didn't say the paperback was worth anything), you better not have read it too much. “This copy is in excellent condition," Haley said of the book up for auction, "one of the very best I’ve seen — and we’re expecting a lot of interest.”

Jill Pantozzi is a pop culture writer and host who reports on all things nerdy and beyond! Her blog TheNerdyBird.com was recently relaunched with Patreon support and she’s formerly Editor in Chief of The Mary Sue. She’s written for MTV, Tor, Playboy, Publishers Weekly, IGN & more. You can keep up with Jill, and her cats, on Twitter at @JillPantozzi.