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The United States Mint has created annual sets of Uncirculated coins for collectors widely known as Mint Sets since 1947. Amidst a few interruptions and several changes in format, this popular collector offering continues to the present day. The useful numismatic product allows collectors to have one example of each coin issued for circulation within a complete set issued by the U.S. Mint.
The first generation of sets issued from 1947 to 1958 included two examples of each coin struck for circulation and are sometimes referred to as “Double Mint Sets.” These were typically issued in low numbers and can now be difficult to find intact and in the original packaging. Those sets encountered in the original packaging, which consisted of cardboard and paper holders, will generally include coins which have developed tonging over time. This type of original toning can be desired by many collectors and can sometimes exhibit attractive rainbow hues.
The next generation of sets issued from 1959 to 1964 came in flat packs similar to the packaging developed for the Proof Sets. Two cellophane packs contained a single example of each coin issued for circulation and were placed within an envelope marked with the date of release. After this run, the issuance of typical Mint Sets was briefly suspended and for three years, Special Mint Sets were issued instead.