The coin is actually a half (medio) Balboa, the size of a U.S. half dollar. These coins were (and, I believe, still are) minted in the U.S. on half dollar sized planchets. The 1962 half Balboa contains the same amount of silver as all .900 silver halves, and is worth about the same as common U.S. silver halves, although far fewer Balboas were minted in '62 than Franklin halves. Morgan dollars have a higher silver content than your coin, as would be expected. Panama, however, also issued silver Balboas, a larger coin than the half Balboa, which may have had more silver than Morgans...I forget. Panama still issues super large silver coins for collectors. Modern medio Balboas are of copper-nickel clad copper; no silver.