A rare copy of Harry Potter and the Philosopher's Stone has been sold for $109,000 at auction.

The book is one of only 500 hardback first editions printed and was sold by a retired British ex-pat from Luxembourg.

Auctioneer Jim Spencer said as the price climbed, it was "astonishing" to watch.

The vendor wants to remain anonymous said that he bought the book for his children around 18 months after it was first published in June 1997.

He said he was "absolutely delighted" with the sale.

"The Harry Potter books are truly iconic - in the very top tier of literature for children - and this first edition can only increase in value in the future," he said.

The vendor admitted he planned to use money from the sale to pay off his daughter's student loans.

The book was identified as a first edition as it has a duplication of the phrase '1 wand' on page 53 and an issue number of "10 9 8 7 6 5 4 3 2 1".

The final bid for the book came from a private international buyer who was bidding by phone.

Mr Spencer said it was the highest price paid at auction for a copy of the book.

"I'm absolutely thrilled the book achieved such an outstanding price for our vendor," he said.