I'm more inclined towards thin planchet.
Is the edge etched?
Is the coin the same diameter as a regular issue? If it is then it is not acid, as the amount of acid required to "thin" the coin would also reduce the diameter.
Even if the diameter is not the same as a regular coin, it could still be from a foreign plancet, that was so small that it could not "fill" the space of a normal cent.
Lastly for that much surface area to be gone I would expect a LOT more detail to be missing.
Is the edge etched?
Is the coin the same diameter as a regular issue? If it is then it is not acid, as the amount of acid required to "thin" the coin would also reduce the diameter.
Even if the diameter is not the same as a regular coin, it could still be from a foreign plancet, that was so small that it could not "fill" the space of a normal cent.
Lastly for that much surface area to be gone I would expect a LOT more detail to be missing.























