Having prospected for gold in the Yukon Territory (see Gold Prospector), and having used a metal detector to search for buried relics, I became intrigued by the legend of John Swift's Lost Silver Mines in eastern Kentucky. I constructed a hypothetical map from "Swift's" purported journal and did some prospecting (with cousin John May who made these photos) in a rock shelter in the Red River Gorge area. However, the scientific evidence seemed to preclude fabulous silver treasure being mined in Kentucky, and I subsequently wrote a lengthy treatise that discredited the Swift tale. (See chapter 5, "Folklore: Swift's Lost Silver Mine" in Joe Nickell, Unsolved History: Investigating Mysteries of the Past, Lexington, Ky: University Press of Kentucky, 2005, pp. 51-68.)
Other treasure quests have involved the Oak Island "Money Pit" mystery in Nova Scotia (see my Real Life X-Files, 2001) and the Beale Treasure legend in Virginia (Mysterious Realms, 1992).