What is believed to be the only surviving, authenticated portrait of Billy the Kid has fetched over $2.3m (£1.4m) at auction in Denver, Colorado.
The tintype went to private collector William Koch at Brian Lebel's 22nd Annual Old West Show & Auction, where auction spokeswoman Melissa McCracken said the image of the 1800s outlaw was the most expensive piece sold at the event.
A 15% fee was tacked on to the bidding price, making the actual selling price more than $2.6m (£1.6m).
Organisers had expected it to fetch between $300,000 and $400,000 (£188,000-£251,000).
The tintype is believed to have been taken in 1879 or 1880 in Fort Sumner, New Mexico.
It shows the outlaw, real name William Bonney, dressed in a rumpled hat and layers of clothes.
Billy the Kid gave the image to a friend, Dan Dedrick, and the tintype has been owned by his descendants, the Upham family, ever since.