This coin is a 1979 Roosevelt Dime, minted at the San Francisco Mint, and is part of the U.S. coin series known for its depiction of President Franklin D. Roosevelt. It is a proof coin, which means it was struck using a special process that results in a high-quality finish, often with mirrored surfaces and sharp details. The dime features a diameter of 17.9 mm and weighs 2.27 grams, constructed with a composition of copper-nickel clad over a pure copper core. Despite the fact that the reported mintage for this specific coin is zero, it is essential to note that it indicates a lack of production figures typically available for the standard circulation coins in the same year. This coin is denominated at 10 cents (or 0.10 USD) and falls under the category of collectible coins, particularly prized by numismatists due to its proof status. It reflects the craftsmanship of the San Francisco Mint, known for producing a variety of proof coins. Given its specialty as a proof coin, this 1979 Roosevelt Dime is likely to be appreciated by collectors and may hold significant value, especially if in pristine condition. Further evaluation of its grading based on surface quality and preservation would aid in determining its precise market value.