The magnificently named Lake Winnipesaukee Mystery Stone is just that — an odd carven stone, about 4 inches long, turned up by workmen digging a fence post in New Hampshire in 1872.

No one knows who carved it, when, or why. On one side are carved an ear of corn, a deer’s leg, and several other figures. One the other side are inverted arrows, a moon shape, a spiral, and some dots.

When the stone first came to light, the American Naturalist suggested that it “commemorates a treaty between two tribes.” But after an analysis in 1994, state archaeologist Richard Boisvert said that the holes drilled in the top and bottom are more consistent with power tools from the 19th or 20th century. He said that scratches in the lower hole suggest that the stone was placed on a metal shaft and removed several times. We’ll never know its real origin.