I have been going through some copper coins tonight, just found this one. Not sure what to think. the coin weighs 3.1 grams thanks
Someone tried to glue 2 coins together. One coin fell off and left that marking. It some sort of some adhesive that stick on the coin. AKA Vise Job.
in 2016, 3402 coins were reported ingested by children to poison control. This is just what was reported to poison control and not at hospitals and clinics nor cases of "unknown" ingestion. You have a better chance of having one of these "special" coins in your pocket change then a true DD. Now thats strange!