The "Calaveras Skull" is found and touted as proof of pre-historic Californians.

Miners discovered a human skull deep in a mine, beneath an ancient lava flow, in Calaveras County in central California. State geologist J.D. Whitney pronounced it as evidence that humans had inhabited California five million years ago.. Rumors quickly emerged that the skull was from a Native American burial and other miners had planted it as a joke.  Carbon dating in 1992 proved the skull to be only 1000 years old. (By John Osborne)