That is a textbook example of what numismatists refer to as "a round thing with a hole in it." It might have started out as a coin, but it's hard to imagine that it could be worn that featureless and still retain a rim, unless the rim was beaten onto it later. How big is it, and how much does it weigh?
All planchets have rims. First they are blanks when they are puched out. When they are upset they receive the rim and are called planchets.////That thing looks more like some kind of machine part.
That is a large cent planchet. With a hole in it. Here is one for a 1843 -1857 large cent from the Dan Holmes collection
Could be a large cent planchet also more likely could've been a slug used in the period to pass as a large cent as a counterfeit
If its a fake they did a pretty good job its the exact same size weight and thickness as the large cent I have I'm not trying to argue with anyone just saying
The response from the gentleman in post #9 is as solid as you're likely to get. If he says it's a planchet, I'd take his word for it.
Maybe, but on the other hand its a bronze disk. Usually the issue with unstruck planchets is PROVING IT. Since its not struck, this is a lot harder than you would think. Without a provenance, its going to take a lot of work to actually prove this item was intended for US coinage, was at one time owned by the mint, and just never got struck for some reason. All of this is required for it to have numismatic value. My advice is to seek out a EAC collector and ask him/her how they would best advise you of authenticating this as an authentic planchet. Short of this, how do we know it was just not a metalshop project at the local high school? That is the suspicion you will be up against. Best of luck Mike, and please let us know how it turns out for you. If it is an unstruck large cent planchet, you have a rare and very interesting item there.
My post was not an agreement because of personal opinion (I honestly don't know), but respect for the person behind it and the in-depth knowledge he has displayed of the type.
I have the utmost respect for the poster as well, and thought it was an excellent suggestion. I was simply explaining the difficulty to the OP in proving it is what we think it may be.