CoinWorldTV 1991, United States. Proof Silver “Mount Rushmore” Anniversary Dollar w. Box! Mint Year: 1991 Reference: KM-229. Denomination: Dollar Mintage: 133,139 pcs. Mint Place: San Francisco Material: Silver (.900) Weight: 26.7gm The 1992 Summer Olympic Games, officially known as the Games of the XXV Olympiad, were an international multi-sport event celebrated in Barce ...