One small part of the graphics was inadvertently not included during production of the coins. This page explains when you will need the missing information and how to get it. (Revealing it early would spoil part of solving.)
Note that this applies only to the physical coins; the coins shown in the printed PDFs are fine.
If you are using ClueKeeper, it will notify you when the omission becomes relevant and explain how to get the missing information without spoiling the solve process.
Return to this page for details on the missing information during your solve of puzzle number two. Begin solving as usual, and after you have figured out the process for solving, look at the description of the omission.