The only thing worse I know of than that are the key date coins with holes or graffiti. So far I've seen an 1893S Morgan with someone's initials carved into it and a 1909S VDB with a hole in it for a chain.
I've got a 1896 DMPL Morgan with this same sort of white fingerprint "toning" on it. The print was probably darker at one time and turned a brilliant white when the coin was dipped.
Comments
well the only worse thing is if you buy that coin!
or buying a coin graded dmpl or dpl that is not a real deep mirrored prooflike coin!!!! and believe me they are out there!!!!
or paying over 2000 2500 for a 66 dmpl coin and it is at best a shallow borderline dmpl/dpl coin and is a low end 66 at best
you really lose your ass on those coins but i guess it is a learning curve that you do not repeat!
sincerely michael