If you’re a fan of all things Hogwarts, you’re probably reading Harry Potter and the Cursed Child (or you’ve finished it, and you’re looking forward to the just-announced Harry Potter books from Pottermore that will be released in early September). But by revisiting the series’ beginning, you stand the chance of scoring some serious cash—that is, if you live in England or purchased your books there.

According to The Independent, 500 hardback copies of the first novel’s original edition—Harry Potter and the Philosopher's Stone, published in the UK in 1997—contain a barely-noticeable typo on page 53. Flip to it, and you’ll find the list of school supplies that first-year wizards are required to purchase for Hogwarts. It features your typical magical classroom fare, including one set of brass scales, one telescope, one set of glass and crystal phials, and a cauldron. But if you look closely, you’ll notice that the list also mentions “1 wand” twice. (A brief reminder: In 1998, the book was released in the U.S. as Harry Potter And The Sorcerer's Stone, so if you own a first edition of the American novel, you won't find the typo.)

The misprint is minor—but rare book experts think it will help one rare, first edition copy of Harry Potter and the Philosopher’s Stone fetch more than $33,000 when it’s sold at London’s Bonhams Fine Books and Manuscripts this November.

That’s a lot of money for a printing glitch. However, as Matthew Haley, Bonhams’ head of books and manuscripts, pointed out, buyers are paying for nostalgia. “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,” Haley told The Independent. “The proof reading error about the wand in the first edition has, of course, become a treasured piece of Harry Potter arcana.”

[h/t The Independent]

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