How to tell a Scratch from a Crack in a Cylinder?

RustyRatRod said
That scratch was made because whoever honed it left the stones too far out when they pulled the hone out of the bore and it scratched it on the way out. Unless you can feel it with your fingernail, I wouldn't worry with it.....but I would run a dingleberry in it and clear it up.

I found an old Pic of that No.#6 Hole from the Teardown last November... The Line was there already when I tore it down.
I think that's why I was worried that it might be a Crack.