The chair JK Rowling sat on to write the first two books in the Harry Potter series has realised $394,000.
It achieved an increase of 755.5% on an opening bid of $45,000 at Heritage Auctions on April 6.
The chair, which features Rowling's decorations, first sold at a charity auction in 2002 where it made $21,000, meaning it has enjoyed growth of 23.3% per annum over the past 14 years.
Rowling was given the chair, one of a set of four, when she moved into a council house in Edinburgh in 1993 following the breakdown of her marriage.
She published Harry Potter and the Philosopher's Stone in 1997. It was phenomenally successful and spawned six sequels - becoming the biggest selling book series in history with 450m copies sold.
James Gannon of Heritage Auctions said in the run up to the sale: "For me, what's important about the chair is that [Rowling] basically created a unique artwork that's self-reflexive.
"It's all about her creation.
"There's not that much in Harry Potter world that's very valuable or very rare because the books were so big so quickly, so after the first couple of books, the first editions were quite large, and I think, by the end, they were printing like 8m or 10m copies of the first edition."
This is not the first time a piece of furniture connected to an author has sold big at auction.
In 2008 the desk at which Charles Dickens wrote Great Expectations realised ?�433,250 (then $850,000).
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