The coin in question is a 1991 Silver Eagle, a cherished collectible within the American coinage series. This particular specimen was minted at the San Francisco Mint, denoted by the "S" mint mark. As a proof coin, it exhibits a high level of detail and a mirror-like finish, making it especially appealing to collectors. Struck in .999 fine silver, with a weight of 31.1 grams (1 troy ounce) and a diameter of 40.6 millimeters, the coin adheres to the specifications of the American Silver Eagle series. With a total mintage of 511,925 pieces, this edition is a notable addition for any numismatic collection. The obverse of the coin features Adolph Weinman's iconic Walking Liberty design, which beautifully captures the spirit of American liberty. The reverse showcases a majestic eagle, a symbol of strength and resilience, designed by John Mercanti. This 1991 Silver Eagle falls under the denomination of $1, though its intrinsic silver value often far exceeds its face value. Collectors appreciate these coins not only for their precious metal content but also for their artistic design and historical significance. Given its proof status and the relatively low mintage compared to some other years, this coin is an excellent choice for both seasoned collectors and those new to the hobby.