1979 Penny Have No Clue What In On The Obverse Side

What would cause that vein. It's raised and.it won't come off.

Dearborn, if that is true would it really bonded to the coin. I don't know the answer just asking. I have one that is similar but different date 2003. Which I have soaked many times in acetone and picked at with a toothpick. And no change.

Water and acetone are both just solvents. Both have certain chemicals/compounds they can and cannot react with. So just like water will not dissolve tar, there are things acetone also will not remove. Xylene is another solvent you could try.

It could be possible, I think, that the copper in this area of the coin was submitted to something that not only reacted with the copper, but combined with it to bond and form the line on top. In that case it is not just a foreign substance on the coin, it is a substance that chemically bonded and integrated into the coin's matrix.

All guesses. But nothing int he minting process can make something look like that. If it had been a part of the planchet, then you would see the design of the penny stamped into it. But this line passes over the top of, and (at least in the pics) seems to spread out over top of the design.