San Francisco cents carry a small S mintmark. The punch used to impress that letter changed many times. Collectors study the profile — height, width, and serifs — because a given year can show more than one style, and some styles overlap across calendar years.
This page is historical reference. When you attribute a cataloged die, use the Design varieties hub for the specific year and mint. Design variety records are where dies are assigned; this timeline explains when each S profile was in use.
Profiles we name on CopperCoins
Clear-S — relatively tall and narrow, with open space inside the curves of the letter.
Block-S — shorter and wider, with a heavier, more “filled-in” appearance.
These are CopperCoins terms. Other references use different names and numbering systems for the same physical punches.
Chronological usage (Lincoln cents)
Below is the sequence collectors use for San Francisco Lincoln cents. Some years show a single profile; others show two (sometimes with overlap as one punch replaced another).
- 1974-S proof — Clear-S first, then Block-S (both on large-date proofs). See 1974 design varieties.
- 1979-S — Block-S first, then Clear-S. See 1979 design varieties.
We will expand this timeline as additional S profiles are documented on CopperCoins. When a year has an assigned design variety for a profile, the design variety page holds identification detail; this page stays focused on when each profile appeared.
RPM on the S is not a new profile
Doubling on the mintmark from a repunched punch is a die variety (RPM), not a third S profile. The timeline lists punch styles; RPM coins stay under their design variety with RPM called out on the die page.
Further reading
Factual year sequences for San Francisco mintmarks appear in several numismatic references. Terminology and organization on CopperCoins are our own.
