This is not corroded at all but he looks like he has acne AND the five is filled is that of any significance Thanks
What date is the Lincoln? Is it copper, zinc, etc? And the Jefferson I believe is common to have that
The lincoln either got real hot or it was struck with a rusty die, which I believe would be highly unlikely.
Most likely on the Lincoln something has gotten behind the copper clad through a hole in the copper and is now eating away the zinc. When Zinc's get dinged and the copper cladding is breached the zinc goes down the tube real quick. Ice
To simply put it, improper cladding on the lincoln. The filled number is common and is the result of a die chip or something of that nature.
