Obverse Dies: 1 Known
For 1864 San Francisco dimes, strike weakness at Liberty's head and the bow knot is common. This date does come better struck than 1863 San Francisco examples. Only one die pair is known. The 1864-S date is the easiest San Francisco date to locate within the 1860 - 1868 timeframe. It becomes rare in Mint State.
Plate Coin: Fortin 101, Well Struck, Light Golden Toning On Both Obverse and Reverse
In 1864, employees at the San Francisco Mint ramped up production of Dimes and stamped out 72,500 more units than in the preceding year. Apparently, this was all done with a single pair of dies, according to Seated Dime researcher Gerry Fortin.
Most 1864-S Dimes are struck well, but those from the latest state of the dies will show some graininess around the date and in other areas of the fields on both sides.
Mint State examples are scarce but not rare. The typical Uncirculated 1864-S Dime is MS64 -- in fact, the PCGS CoinFacts Condition Census starts at MS64 and tops out at MS67. Like the 1864 Dime, the 1864-S appears to be an excellent value in most grades.
Northern Bay Collection - Stack's 3/2006:4287, $32,200 - Eugene H. Gardner Collection - Heritage 6/2014:30262, $25,850