Nice lamination! I don't think you're seeing things but I do believe it would come off with some cleaning. Probably remnants of a combination of a stacked coin and glue or some other substance. If so, the number would actually be a "9", or upside down 6
Yay! Well, I'm Learning quickly.
I study every aspect of the coins. The slightest variation appears to me instantly.
It is a curse, but comes in handy when looking at coins..
I have eidetic memory.
We actually get a special label..
I'm an Eidetiker.
Nice lamination problems on that coin. Congrats! I can't be sure but it appears that what looks like a "6" is actually more of the coin's surface starting to bubble and separate or in other words, another lamination error.