To be sure of what?
A scale which weighs to 2 decimals would be more helpful. This is most likely a copper cent within weight tolerance. If the color in your photo is...
Sorry, I cannot say how common. I have seen it.
Rim Beveled Strike was not strong enough to eliminate completely the original beveled junction between the planchet’s proto-rim and edge.
It looks to me like your quarter has environmental discoloration. Were it missing clad, weight would be less than normal. Quarter weight missing...
Looks like Radial Flow Lines beginning to show. http://www.error-ref.com/radial-flow-lines/
You are correct...it is quite common! If something happens during the minting process, I enjoy knowing what happened even if it is common and adds...
Struck through grease is an error type - although quite common. I think Mike is saying this quarter is one of the forms the strike through takes....
Behind the damage is a poorly struck perimeter - especially prevalent on 1985-D dimes. This is discussed in a Coin World article: Many dimes from...
Seems to be common on ATB quarters. Quarter Struck Through Rearranging Foreign Material Mike Diamond “…this would be a "struck-through" error in...
Please - photos of both sides of the whole coin
Are you able to provide the photos needed for the overlays?
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You are correct! I am one who thinks a scale which weighs to 2 decimals in grams is a necessary requirement for a serious collector's toolbox, and...
I agree that it is damaged. If he weighed the coin it might help convince him that your assessment is correct.
Weigh the coin!!! (Please)
Tin shears or some such tool
I agree with all the above. A first step in understanding what you have is to weigh the coin. For example, a cent struck on a cupronickel alloy...
I asked the mint what the tolerance was for die rotations. Here is their answer: "For circulating denominations the coin rotation tolerance is...
Scroll down to “Zinc Rot” where you will see examples similar to yours: http://lincolncentsonline.com/pmd.html
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