If you can't see it at 10x it's nothing. If you examined ever coin at 500x, every coin would have an error or an anomaly.
my microscope goes up to 500 x . i spotted the mint mark error by just looking at the quarter, then getting out my 10 x magnifier, also have 30 x 36 magnifier... i've never macro a coin.. the scope is about 1 1/2 inches from the coin....the microscope has about 5 " adjustment . i could put it up a lot higher, but the picture is distorted some..... Thanks for the info