Coins that have letters and numbers added are common, but it does not add to the value of any coin. 1957 is not a rare year for a Washington quarter so the value is just for the silver, about $5.00
They're called Washington quarters because they carry a picture of President George Washington
George Washington
George Washington
George Washington
George Washington is on top of a Quarter.
For U.S. quarters it's George Washington, from 1932 to 2011.
George Washington
George Washington
George Washington
George Washington :)
George Washington
George Washington.