2523. The American Mint 0.5 Gram 14K Gold Proof Round featuring Our National Anthem is a solid gold collectible from 2009. This limited edition round has a fineness of 0.585 and contains 0.5 gram of precious metal content. Produced by American Mint in the United States, this unique piece is a part of a complete collection of 9999 rounds, making it a valuable addition to any collector's inventory.