* Look at the mint mark. The mint mark is a small letter or symbol that appears on the back of a penny. It indicates the mint where the coin was produced. The following table lists the mint marks and their corresponding mints:
| Mint Mark | Mint |
|---|---|
| P | Philadelphia |
| D | Denver |
| S | San Francisco |
| W | West Point |
| O | New Orleans (closed in 1909) |
| CC | Carson City (closed in 1893) |
* Check the reverse of the penny. The reverse of a penny features a design that commemorates a specific event or person. The location of the event or the person's birth or death place is often included in the design.
For example, the reverse of the 2009 Lincoln cent features a design commemorating the 200th anniversary of Abraham Lincoln's birth. The design includes the words "Springfield, Illinois," which is Lincoln's birthplace.