One of seven handwritten copies of JK Rowling's The Tales of Beedle the Bard is valued at £500,000 ($627,010) ahead of a December 13 sale at Sotheby's.
The author personally wrote and illustrated the books in 2007.
She gave six out to friends and colleagues who'd supported her during the writing of the Harry Potter series.
The other was sold to at auction in 2008 to raise funds for her charity, Lumos. It made £1.7m ($1.9m).
This copy is dedicated to publisher Barry Cunningham, who signed Harry Potter and the Philosopher's Stone to Bloomsbury.
Rowling writes: "To Barry, the man who thought an overlong novel about a boy wizard in glasses might just sell … THANK YOU."
Dr Philip W Errington, head of Sotheby's books and manuscripts department, said: "The personal resonance of this book makes this both an exceptional and highly desirable object to come to auction.
"It is particularly special as it is only one of six made for those closest to the author throughout the journey of creating the Harry Potter series, gifted to the man who recognised the brilliance of JK Rowling's writing and her potential impact on children's literature."
Cunningham is selling the book with Rowling's backing and plans to donate part of the money to Lumos.
We expect it to at least double its estimate.
We have a great selection of rare books and manuscripts for sale.
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