Ron Guth: 1976 was the 200th anniversary of the signing of the Declaration of Independence. Though actual independence was not won until the end of the Revolutionary War in 1783, the year 1776 has always held a special place in the hearts of Americans. Thus, it was felt fitting to create a numismatic tribute to this special anniversary and new reverse designs were created for the Washington Quarter, Kennedy Half Dollar, and Eisenhower Dollar. The obverse of each coin bore a dual date (1776-1976); the reverse of the Half Dollar featured a frontal view of Independence Hall in Philadelphia, where the Declaration was signed.
Bicentennial Half Dollars were produced in 1975 and 1976 in the usual copper-nickel "clad" versions, but also in a resurrected 40% silver "clad" alloy (same as on the 1965-1970 Half Dollars). Both Mint State and Proof version were made. No 1975-dated Quarter Dollars, Half Dollars, and Dollars were made, thus Proof and Mint Sets from 1975 contain Cents, Nickels, and Dimes dated 1975 along with the three Bicentennial Coins. Special, three-piece sets of the silver Bicentennial coins were sold at a premium to collectors.
Despite large-scale destruction of the Bicentennial coins in silver melts of subsequent years, they remain common today. The copper-nickel "clad" Half Dollars are extremely common, and should remain so for decades to come.