The collection consists of a set of Proof coins from the Penny to the Half Dollar for each of the five decades from the 1960’s to the 2000’s. The 1960’s Half Dollar is 40% silver and was the last U.S. coin struck only in silver. • Proof coins are never seen in circulation. They are specially struck for Proof Sets issued by the U.S. Mint.• Proofs are the highest quality U.S. coins and are among the most prized of all coins.• Each coin is struck multiple times under high pressure to bring out the three-dimensional designs and mirror-like background. Due to the painstaking minting process, they are limited editions.• Proof coins are made only at the San Francisco Mint and bear the historic “S” mint mark.• The collection is both a record of the best U.S. coins over a half-century period, and a symbol of the great people and events from that era – from civil rights and the first manned moon landing in the 1960’s to the dawn of a new era in the 21st century.8.5" x 10.625" x .25"