I have these coins and it seems something is in therebut I don’t know what it is. Could someone help?
These are called die cracks. They're fairly common occurrences but still cool to find. They likely won't get you any real premium, but I keep the ones I find. @Fred Weinberg I noticed that error-ref doesn't have a simple "die crack" listing in the index of entries, explaining how they occur before listing out some of the more complex cracks.