Are there any books that discuss how to plate on coins? C.A.
Coin blanks are plated all the time. The U.S. penny is an example of this. However, I am not aware of any books that discuss the process of plating on coins after they have been minted.
Brush plating (electrochemical metallizing) is a technique that should work. The use of brush plating for this purpose is mentioned in the paper, "Cosmetic Brush Plating," Sur/Fin 93, Session E, 1993 by Robert Brookshire. Contact the American Electroplaters and Surface Finishers Society (AESF; 407-281-6441) to get a copy of this paper. This approach is rather labor intensive and probably would work well for a small number of coins.
If you were thinking in terms of a larger number of coins, a process using photo-resists (similar to the processes used in the electronics industry) should work well. I do not have any specific references to the use of this process in the plating of coins.