Die rust is a relatively new discovery among variety coin collectors. It is assumed that dies exhibiting rust were in storage for some time prior to or between use. Most of the rusted dies identified are on the reverse. It is easy to imagine that a stockpile of reverse dies could occur, given that they were consistent from year to year. The obverse dies took extra preparation by adding the date, and could not be stored for use in another year once the date was punched. Mint photos reveal that dies were annealed, hubbed, and punched in large batches.
Rusted Dies of the Indian Head Cent Series
The ambitious collector will want an example of each known specimen exhibiting die rust. They really are splendid. To see the most current list of rusted dies, just click here.