Found this today, been trying to figure out a value on it. The exact error, I believe, would be a double-struck large broadstrike. The closest auction result I could find to this is a double-struck broadstrike, which doesn't have as large a planchet as this, or at least it doesn't appear to have as large a planchet as this. If my terminology is incorrect, I am sure somebody will jump in and correct me in short measure! http://coins.ha.com/c/item.zx?saleNo=402&lotIdNo=148037 And here's some pictures of it...
I've seen one like that - I forget what the error nerds call it. Fancy Double Broadstrike something or another.
My analysis... Your coin was struck once properly (in the collar). It didn't exit the striking chamber properly, and was subsequently struck a second time, but this time not in the collar... Creating a double-struck w/ broadstrike error. As far as value goes, I'd guesstimate that it'd fetch $125-$150 in a retail setting.
