A rare tintype photograph of Frank and Jesse James is to lead a sale at J Levine Auction & Appraisal in Arizona on July 31 with an estimate of $40,000-60,000.
The rare lot is one of only a handful of surviving photographs of Jesse James, another example of which sold for $51,240 in 2011.
It's thought to originate from Nebraska City and was taken shortly before Frank enrolled in the confederate Missouri State Guard at the opening of the American civil war.
The brothers would later fight together as bushwhackers, or confederate guerrillas, and took part in the infamous Lawrence Massacre - where men under the command of William Quantrill murdered 200 civilian abolitionists.
They would go on to form the James-Younger gang and carry out a string of violent crimes throughout the United States.
The lot has been displayed in Ziebarth's Farm Museum in Nebraska for the past 100 years.
An 1884 photograph bearing the signature of five major figures from the Dodge City war (including famed lawman Wyatt Earp) is valued at $10,000-15,000.
The 1883 war pitched the town's old guard, known as the Dodge City gang (which included Earp), against newcomers who intended to take over the lucrative whisky trade.
Matters came to a head when a brothel owner named Luke Short was evicted. He returned shortly afterwards following a show of force from the gang and resumed his business.
The conflict ended without any deaths although, as this was Dodge City in the late 1800s, shots were fired.
This June a book of signatures collected in Tombstone, Arizona made $68,750 at Heritage Auctions.
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