A faded photograph last seen three decades ago at a yard sale in south Georgia could be a historic treasure — the only known image of the armored Confederate warship CSS Georgia.

It's been 150 years since the CSS Georgia was scuttled in the Savannah River to keep it from the hands of Union troops capturing Savannah. The Army Corps of Engineers plans to raise the sunken ironclad's remains this year.

Archaeologists working on the $14 million CSS Georgia project are also trying to locate a photograph that experts say may depict the battleship.

John Potter says he stumbled onto the photo at a Waycross yard sale in the mid-1980s but didn't have $175 to buy it. Potter took photos of the original that he's shared with historians and researchers.