The silver content in United States 50-cent pieces, commonly known as half dollars, is determined entirely by their year of mintage. There are three distinct eras of silver composition for these coins intended for general circulation.
Any half dollar minted in 1964 or earlier is composed of 90% silver and 10% copper. This includes several classic designs, such as the Walking Liberty Half Dollar (minted from 1916 to 1947), the Franklin Half Dollar (1948-1963), and the first year of the Kennedy Half Dollar (1964). These coins are often referred to as "junk silver" and are valued for their high precious metal content.
From 1965 to 1970, the composition of the Kennedy Half Dollar was changed due to rising silver prices. These coins are not 90% silver but are instead silver-clad, containing an overall composition of 40% silver. They consist of outer layers of 80% silver and 20% copper bonded to an inner core of primarily copper and nickel.
Beginning in 1971, the U.S. Mint eliminated silver entirely from all circulating half dollars. Any Kennedy Half Dollar intended for circulation dated 1971 or later is made from a copper-nickel clad composition and contains no silver.
It is important to note that the U.S. Mint has produced special collector versions of half dollars containing silver after this cutoff. For example, Bicentennial half dollars dated 1776-1976 were struck in a 40% silver version for collectors. Furthermore, since 1992, the Mint has issued annual silver proof sets that include a Kennedy Half Dollar struck in 90% silver, and in more recent years, 99.9% fine silver. These special issues, however, were not meant for general circulation.
