1945-S Micro S

The 1945-S Micro S is one of the most popular varieties in the final year of Mercury Dime production. San Francisco used two different mintmark punches during 1945, with the standard knob-end S applied to most coinage and a noticeably smaller S punch used on a portion of production. The smaller punch originated from early twentieth-century Philippine coinage struck at San Francisco, where the small coin size required a correspondingly small mintmark; San Francisco borrowed the Philippine puncheon during wartime production when the standard domestic S punch was unavailable or worn. With Franklin D. Roosevelt's death in April 1945 and the planned debut of the Roosevelt Dime in 1946, the 1945-S Micro S also carries the distinction of being among the final San Francisco Mercury Dime varieties. Mintage is included in the broader 41,920,000 total and was not separately tracked.

The Weinman design carries Liberty in her winged Phrygian cap on the obverse and the fasces with olive branch on the reverse. The diagnostic feature is the mintmark, which on the Micro S variety measures notably smaller in overall diameter than the standard 1945-S and shows a different font shape, with thinner curves and a more compact knob structure. PCGS and NGC both attribute the variety on certified slabs, and side-by-side comparison with a standard 1945-S is the most reliable visual check. The variety is cataloged as FS-512 or similar in the Cherrypickers' Guide. The coin weighs 2.5 grams of 90% silver and 10% copper, measures 17.9 mm in diameter, and has a reeded edge. Central horizontal bands on the fasces must show complete separation for the Full Bands designation.

The 1945-S Micro S commands strong premiums over the standard issue across all grades, with Heritage Auctions recording four-figure results for Gem Full Bands examples. Original surfaces with consistent luster across the cheek, wing, and reverse fields are the strongest signal of long-term holding value. The Mercury Dime series history adds context.