If the lines are raised, those are die polish lines on the reverse. The easiest way to understand this is to look at how the coin is manufactured. On a coin die, the devices are sunk into the die and the fields are flat. If you were to run a wire brush over the top of the die, it would brush just the fields and not the devices.That's why the lines disappear under the Lincoln Memorial, and the letters.
There is a quarter in the C.P.G. It states it could be a remnant of a lapped die , what ever that means.
If it was lapping , I would hate to see what grinding would do. As a facetor, I use laps charged with diamond grit to smooth and polish the surfaces, I assume for metal working it would be the same. I think the working die that produced the cent was ground down or partially destroyed, but someone accidentally ( or more likely on purpose} pressed it with a transfer reverse die and then struck a few coins for fun and profit.
No problem. I have seen several like that. Mostly quarter's. Your's is the most dramatic I've seen on a cent.
Lapping in metal works is used to flatten, level or polish a surface which is either done by hand or by machine. When done by hand the micro-scratches would typically be in a circular direction and more than likely the same by a machine. In order to "Polish" anything you would want to have circular motions to keep from have any repeating patterns which would be counterproductive in the objective. On this coin those lines are not due to lapping or polishing. The lines appear to be fairly deep and they are very straight and uniform. This would have been caused by either being pressed into the die or a one time grazing contact with something else. Really Cool Coin Though!
These aren't un common I see them regularly. The thing that sets yours apart, is the area of damage. and the grade of the cent.
