“American Animals” may not have been the blockbuster film of the summer, but it told the fascinating and true story of 20-year-old Warren Lipka, who planned a daring theft in Lexington, Kentucky, in 2004.

Lipka recruited a trio of friends to help him pull off a robbery that he said would net them more than $10 million. The target was a treasure belonging to Transylvania University: the Havell edition of John James Audubon’s “The Birds of America.”

“There were only 200 complete sets that are known to have been made,” said Marc Fagan, a director at New Orleans’ Neal Auction Co. and an expert on Audubon (1785-1851). “One of the four volume sets sold in 2013 for $11.65 million, and single images can sell for as much as $125,000.”

Fagan should know, for in the course of the 14 years he has worked at Neal Auction, the company has sold millions of dollars’ worth of Audubon prints and has earned international recognition as a leading auctioneer of the works.

On Saturday and Sunday this weekend (Sept. 15 and 16), the Magazine Street auction gallery offers half a dozen works drawn from what is known as the “first edition” or Havell edition of “Birds of America.”

Named for engraver Robert Havell, the edition was produced in London using engravings on copper plates based on Audubon's original watercolors. Audubon and his sons were directly involved in the process, which yielded black and white images for hand-coloring to match the originals as closely as possible.

“Audubon had to take the watercolors to London and to Havell because there simply weren’t any presses in the United States in the early 19th century capable of fulfilling his vision,” said Jane Toczek of The Philadelphia Print Shop, a revered art dealer in Chestnut Hill, Pennsylvania. Lizars of Edinburgh made the first 10 plates before a workers’ strike ended their involvement and Havell took on the job. “Audubon’s determination was astonishing. He was committed to seeing the works reproduced life-size — that’s the reason for the double elephant folio format.”

“Double elephant folio” refers to the size of the sheet of printing paper used. Each one measures 39½ inches by 26½ inches.

“Even using double elephant paper, it was sometimes hard for Audubon to fit the whole image on a sheet — that's why some of the birds are posed the way they are,” noted Fagan. “The Havells are the most valuable of the Audubons because of their size and quality.”

The New-York Historical Society owns Audubon’s original watercolors upon which the Havells are based, having bought them in 1863 not long after the subscription-based set was completed. Although the images are generally referred to as watercolors, Audubon used a variety of materials to produce the effects he desired — pen, pastel, watercolor and even egg whites.

Audubon often depicts smaller birds against solid backgrounds, perched on the branches of trees, possibly nibbling on fruit and berries. Larger birds — such as the Louisiana Heron — are presented in the context of their native habitats.

Several artists are known to have assisted Audubon in creating the backgrounds, including Joseph Mason, who traveled to New Orleans with Audubon from Cincinnati and worked with him for about two years. The second was George Lehman, a landscape painter from Pennsylvania who not only worked on backgrounds but completed a few watercolors of birds. The third was Maria Martin of Charleston, who had made watercolors of plants before she met Audubon and learned how to imitate his style painting birds. Sons Victor and John Woodhouse also assisted and won their father’s praise in so doing (according to Marshall B. Davidson in the introduction to the 1966 New-York Historical Society publication “The Birds of America”).

Changes in Audubon’s technique (he was seldom satisfied with his work and frequently repainted images) as well as the succession of assistants helps date the creation of an original image when a date is not documented. It is estimated that just 120 of the original 200 Havell sets still exist, and of those, just 13 are believed to be privately held. In June, one of those sets —  previously owned by the duke of Portland, then the Knobloch Foundation — sold for $9.65 million at Christie’s in New York.

Although the Havell edition is the platinum standard for Audubon prints, two additional editions also command respect.

“The Royal Octavo edition features images that are much smaller than the Havells but are hand-colored. They are lithographs, and Audubon was involved in making them. These were printed in New York and Philadelphia starting in the 1840s,” said Fagan. “After that, Julius Bien made double elephant folio size prints that relied on chromolithography — the color was printed on the paper rather than applied by hand. They were also released by subscription like the Havells were.”

Although the Bien edition prints aren’t of the same quality as the Havells, their scarceness means they command high prices.

“Many of the subscribers for the Bien edition lived below the Mason-Dixon Line,” said Toczek. “The works began being released to subscribers in 1858, but when the Civil War started in 1860, production stopped. That means only 105 plates of the Bien edition are in commerce, versus 435 in the Havell.”

Many factors can determine the sale price that a particular plate will fetch at auction.

“Condition is one factor — how often or how long it has been exposed to light and therefore how intense the colors are,” said Fagan. “Also how much it has been handled — are there tears or smudges? Over time, some sheets were cut down for framing purposes. They are much more valuable if the paper is still intact. And then there is fashion: For quite some time the wild turkey was the most popular of the plates. One of my favorites is the Louisiana Blue Heron (at auction this weekend). Having said that, for the last 10 to 20 years, the American flamingo seems to draw the most interest and highest price at auction.”

Toczek agreed: “There is no doubt about it: The flamingo is a hottie.”