1958 Lincoln Wheat Cent Mint Error - Split After Strike

I am certainly onboard with something like that being the root cause for this coin. I've looked at it a couple times now and the one thing that keeps me from believing it is an error coin is the separation lines on the reverse. Usually there is at least somewhere you can see a crack extending a little bit under the unaffected area, but on this coin I really just don't see that. It's somewhat smooth, and that's troublesome and leads me to think it's PMD. The detail softness is also pretty similar to an acid-dipped coin, although usually there is at least some pitting. The diameter isn't greatly shy, just 0.1mm, but in the Coin World that's a lot so also leads one toward the PMD answer. Still not sure, but for now things seem to be drifting toward damage.

I would agree with those who suggest that the blurry features are due to contact with a corrosive chemical.

Sap =

You can see in the close-up how the metal was melted along the seams. A laser could also pull this off at the right power level - that could even be more likely. A lamination would have a sharp, jagged edge. I also believe too much metal was removed, delaminations typically very thin - PMD.

Look at the edge of the this retained lam: