I don't think any of us are in any big hurry. Quite honestly we know how it will come back, it is really for your peace of mind. Best of luck.
Pure nickel is magnetic, hence pure nickel plating is magnetic.
Agreed on the nickel plating. This would also account for the slight extra weight.
Using that rationale, do an ebay search for "no mintmark" you will find dozens of common Philadelphia minted coins for sale, and even many that...
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