The clue is an S above the D
On a 1944-D/S FS-511 penny, look below the date on the front for the top of an S rising above the D. The S is the earlier mint mark on the die. A later D punch partly covered it, leaving the high S as the key comparison.
This is an overmintmark, often shortened to OMM. It is a die variety: a difference in the steel tool used to strike the coins. The D/S name does not mean a finished penny was struck once in Denver and again in San Francisco.
Use a fixed reference for the high S
In his PCGS CoinFacts description, Ron Guth places the old S above the D and describes part of the S within the D's upper opening. Compare both features together. A thick rim on a D, a scratch or a dark spot is not a substitute for that pattern.
An original Heritage catalog entry for lot 4638 also describes the upper S above the main D. That description supports the feature to examine. The grade and condition of that auction coin do not describe a different penny in your hand.
Keep four different questions apart
Start by reading 1944 and finding the mint mark. Then decide which feature you are testing. A possible overmintmark is not the same problem as a coin struck on the wrong metal blank.
| Possible feature | What to examine |
|---|---|
| D/S, FS-511 | The high S and the matching detail within the D. |
| D/D | A repunched D, involving the same letter. |
| A steel-colored 1944 cent | A separate metal and authenticity question. |
| A doubled date or motto | Design detail beyond the mint-mark comparison. |
CoinHub's 1944 wheat penny guide covers the separate steel-cent question. A magnet or weight reading does not establish the high-S variety. Likewise, finding a possible S does not prove a coin is steel.
Photograph the evidence before naming a value
Take one clear image of the whole front, then a closer view that keeps the date and mint mark upright. Try light from a second direction. If the supposed S vanishes into glare or a scratch, keep the match uncertain.
Save the source reference with your photos and note what remains unclear. Do not clean the coin to make a letter stand out. A professional review may help settle a close match; a sales claim should follow the evidence rather than lead it.
FS numbers belong to specific varieties. The 1951-D/S FS-511 penny is a different dated issue, even though its catalog number looks familiar. For broader background, CoinHub founder Blake Alma's The CoinHub: An Ultimate Guide to Coin Errors is an optional book from our own publisher. The specific 1944 reference remains the starting point here.