Ok I was searching through a coin jar today to replace a few quarters I pulled out of a roll and came upon 15 rainbow toned Lincoln cents. And that was out of about 300 cents. My question is, are they common to find? I also noticed a pattern of sorts in the dates. They were all dated 1978-1988. Kinda weird, but maybe just coincidence.
It isn't a rare thing. From personal experience, the majority of the rainbow toned lincolns are actually caused by a foreign substance. Meaning, the coin itself is not toned, but finger oil or something else on the coin is toned. Show us some pictures though!
I will try to scan 'em when I get home from work. Just started a job a week or so ago. I did also find one golden colored cent and a very light woody.