A print from James John Audubon's Birds of America has sold for $85,400 at a books and manuscripts auction in Chicago.

Audubon's working proof of the great blue heron came in comfortably within estimate, and is further evidence of the huge popularity of his works at auction.

Birds of America's is the world's most valuable book

Completed and published over 11 years from 1827 to 1838, Birds of America is considered the highest achievement in ornithological art.

It is the world's most valuable book, with one of the 200 elephant folio copies produced having sold for £7.3m last year.

The full sheet print at yesterday's (August 8) auction differs from the published edition, with blue rather than grey colouring to the heron's body, and alterations to the bird's feathers, which are highlighted in green, as well as changes to the thigh and bend of the wing, which is russet rather than orange.

It also lacks the engraved lettering and plate numbers of the published version.

Several repairs to the edges and a small filled hole were the piece's only detractions.

We expect the piece to provide a superb mid- to long-term investment for its new owner, such is the popularity of Audubon's Birds of America works. You can view other investment-grade books and manuscripts here, courtesy of Paul Fraser Collectibles.

We will bring you more from the auction shortly, so be sure to check back soon.