1964-D 50C MS68 Certification #21637941, PCGS #6707
The 1964-P and D Kennedy Half Dollars were composed of 90% silver, therefore making them a one year type. The following years, or from 1965 to 1970 circulation strike Kennedy Half Dollars were struck in 40% silver.
The 1964-D tends to be better struck than the 1964-P as there is atleast one known example grading up to MS68 condition for the 1964-D.
90% Silver, 10% Copper
The United States of America