卞和 of the state of
楚国 found an uncut stone and offered it to two kings in turn; each was told it was a plain rock and had one of his feet cut off. The third king had it cut open, found fine jade inside and named it after him. Later Qin offered fifteen cities for it, the source of
价值连城, and
蔺相如 carried it safely back to Zhao, the source of
完璧归赵.