Today I decided to calm my nerves and look through a small bag of wheat pennies I purchased at a yard sale last summer. I dumped out the dirty little zip lock bag to find a treasure trove of rainbow toned beauties (In My Opinion). Most of the dates are from the late 40's into the 50's, with various mint marks. They are all in various conditions as well. Nice find I think.. Anyhow they brought a smile to my face nevertheless. I thought I would share. Hard to get a decent photo of them though.
To me they look like they were cleaned at some point and have gained the colors because of the way they have been stored. Heat may have been involved.
I have seen this kind of color on cents that have been in a cigarette smoker environment for many years.