I have two Jefferson Nickels, a 2006 P and a 2005 P {Pacific Coast} that have blemishes. I think these were caused by something on the die when struck. But what is the official term I should be using? 2005 P {Pacific Coast} 2006 P
@tomd- Like @physics-fan3.14 said, the official term is called struck through grease. Unless you have a lot of them, I wouldn't spend it. Just keep it as a good example of Struck Through Grease.
I have a Mac first, a PC should be able to do this also. I open my doc program {Pages for Mac} and insert a arrow. Then copy it to my clipboard. I have my image open {Preview for Mac} and past it. I have not found out if there is another way to do this yet. I am sure there is and someone can let us know of an easier way to do this.