Realcent.org

Hey,

I got 3 wheats from a box today that were all in fantastic red condition except for a weird rainbow type of corrosion. It's definitely not going to come off, it's not a dirt thing. Just wondering if you guys have any idea what this is from? Can't scan right now, sorry.

Thanks in advance,
Atticus

You sure it's corrosion and not toning? Rainbow colored toning on clean copper is not that uncommon. I have seen bright lime greens and brilliant magentas and everything in between.

It's called "toning". It can be very appealing to some collectors. You should never try to clean any coins you own.