Mint engraver Charles Barber designed the first Liberty head halves, as well as dimes and quarters. These “Barber Halves” were primarily composed of silver and were produced in 1892-1915. In 1916, a “Walking Liberty” design was implemented. The design was again changed in 1948 to showcase founding father Benjamin Franklin. Since 1964, half dollars have featured the profile of President John F. Kennedy. Though halves were composed of 90% silver through 1964, from 1965-1970 they were 40% silver.