The 1965 US Mint Special Mint Set in Original Envelope contains uncirculated silver 50 cent coins struck in San Francisco. These coins have a composition of .4 fineness silver and are certified by the U.S. Mint. This set provides collectors with a valuable addition to their US coin collection, showcasing the craftsmanship and quality of the coins minted in 1965. The original envelope adds to the authenticity and historical significance of this unique set.