Hi.I found a 1969 D penny with an error I can't find anything about.This coin is about 1/3 the thickness of a regular penny,(see photos)and only weighs 1.8 grams.As you can see by the pictures the front is hard to see but the back is very clear.My question is ,is this a common error and where can I get an appraisal at?Does the front being worn make it worthless?I'm new to this sort of thing,so any help would be appreciated .thank youName:  100_0830.JPG
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