KWJ asks” What is a clad quarter?
Quarters minted from 1965 to the present are struck on blanks that have the following composition:
Outer layer of copper-nickel alloy (.750 copper and .250 nickel) bonded to an inner core of pure copper. This sandwich of a CuNi layer on each side of the coin with the copper core in the center is called clad composition.
Dimes, quarters and dollars from 1965 and half dollars from 1971 to 1999 are struck on clad blanks. The new dollar coins that were issued beginning in January 2000 are the first to depart from this formula. See: United States Clad Coinage