1999 Lincoln's Ghost Penny ? Error ?

I have a 1995 will that on only half of the rev by one cent. I think it from being in a roll that has gotten wet?

That's what it is - environmental damage, probably from a roll that was stored improperly.

definitely environmental damage - I wouldnt call that an error of any kind. Still cool though

livingdinasaur - Your wheats are a different effect and are caused by the mint. They aren't errors, but are sometimes interesting nonetheless. They are caused by die wear - constant pressure where the two dies meet tend to pass their impressions to one another after a few hundred thousand strikes. The molecules of the steel die change in alignment with different forces of pressure, and eventually start chipping away unevenly. Often this uneven chipping will show best where there are grave changes in relief on the die - like around the bust. The result is a ghost indentation of Lincoln on the reverse in the fields.

What we are looking at in this thread is a coin with coloration of another coin showing on the devices. There is no change in relief where the color changes occur. This is a simple case of a wet coin transferring a chemical change to another coin due to whatever caused the moisture...often laying in rust, heavy ferrous content water, or water with chemical treatment such as fountains or swimming pools. foundinrolls stated the most common place where these come from - wishing fountains in malls and parks. These fountains are usually treated with chemicals such as chlorine, and often contain rusting steel plumbing that will act corrosively on the coins contained in the water with the rust.

Great thread! Really enjoyed the info.