National Geographic : 2012 Mar
Looking as if it fell from the sky, a 40-ton erratic stands on the Colville Indian Reservation in Washington State. Such boulders are sometimes called rubbing stones because bison scratched up against them. "Leaverites"---leave 'er right there---is another nickname for erratics too big to move, like the one by a parking lot in Mystic, Connecticut (le ). But developers haven't always le 'em right there.