During the changeover from silver to copper-nickel coinage, the Mint stopped putting mint marks on all denominations of coins. The idea was to reduce the number that were being removed from circulation by collectors, although in reality that's just a tiny fraction of overall production.
The Kennedy Half Dollar was first minted 1964, in 90% silver.
All half-dollars minted from 1964 to the present bear an image of John F Kennedy.
Not counting commemoratives and other coins minted for sale to collectors, the last half dollar minted in solid 90% silver was the 1964 Kennedy Half. 1965 through 1970 Kennedy halves have a copper core and 80% silver outer layers for a net silver weight of 40%.
The last half dollars that carried a picture of Miss Liberty were minted in 1947. All halves minted since 1964 have a picture of John F. Kennedy and are called Kennedy halves. There's more information at the Related Question.
Eisenhower Dollars were first minted in 1971.Perhaps you are thinking of a 1969 half dollar. 1969 was the last year that the Kennedy Half Dollars had silver. 1965-1969 Kennedy Half Dollars contain 40% silver.
It will have a D mintmark. '
The Kennedy Half Dollar was first minted 1964, in 90% silver.
Kennedy is on the HALF dollar, not dollar. There were no U.S. silver dollars minted in the 1960s. The '64 Kennedy half is 90% silver and extremely common, currently worth about $10.50 for the silver.
All half-dollars minted from 1964 to the present bear an image of John F Kennedy.
The Denver Mint made less coins.
They're still in production as of 2017, but only to satisfy the collector market. The last year they were minted for general circulation was 2001.
Not a lot. The 64 is the only 1 that is really desirable.
Not counting commemoratives and other coins minted for sale to collectors, the last half dollar minted in solid 90% silver was the 1964 Kennedy Half. 1965 through 1970 Kennedy halves have a copper core and 80% silver outer layers for a net silver weight of 40%.
Eisenhower was on the DOLLAR coin in the 1970s. KENNEDY has been on the half dollar since 1964. A 1985 Kennedy half is still worth 50 cents.
A Kennedy Half Dollar that was minted in 2007 and carries a mint mark of "S," was produced in clad and silver. The clad in a proof state is worth: $4; in silver, the value is: $7.00.
Kennedy halves are still being minted. They haven't been put into circulation recently because of low demand but they're made available to collectors.
The last half dollars that carried a picture of Miss Liberty were minted in 1947. All halves minted since 1964 have a picture of John F. Kennedy and are called Kennedy halves. There's more information at the Related Question.