I agree with @Wheatmaster101, but voted for 9 in your poll. I’m pretty certain that 9 will be the eventual winner.
What you are seeing is the inner zinc core of modern cents. I couldn’t say what dissolved the copper coating, but that’s what you have.
This. It's hard to say what sort of environmental damage took the copper plating off. Probably something acidic, because whatever removed the copper took it off pretty evenly, which is a bit unusual. I'd have thought maybe this happened from being in the ground, but in my metal detecting experience with buried zinc cents, they tend to become much more pitted and corroded than that. So I suspect acid, maybe. It's likely only worth one cent, but still an interesting find. I also voted "9" in the poll. For both "9" options. It seems the second "9" is in the lead. (What do the nines mean?)
It’s German as in “Has any silver cent ever, in the history of CT been worth more than one cent, NEIN!”