The 1870-S Liberty Seated Half Dime represents a unique rarity in American coinage. Although no half dimes were reportedly struck at the San Francisco Mint in 1870, a single example is known to exist. The coin surfaced in a dealer’s junk box of generic coins in 1978 and was first shown to the public at the 1978 ANA convention in Houston, Texas.
The cornerstone of the new San Francisco Mint was laid in 1870, and it is believed that this piece might have been struck to commemorate the event. Although it has never been confirmed, it might be possible that a second piece remains in the cornerstone of the building as part of a complete set of 1870-S coins.
The single known 1870-S Half Dime is currently graded PCGS MS-63, but was first graded as AU-55. The coin exhibits proof-like fields with original toning. This enigmatic coin last sold privately for $1.4 million.
- Designer: Christian Gobrecht
- Composition: 90% Silver, 10% Copper
- Weight: 1.24 grams
- Diameter: 15.5 mm
- Edge: Reeded