Hello and welcome.

While I'm sure everyone is going to be saying "we want to see pics", I think from your description in this case, we can make some general assumptions.
If:
- Your coin is an American 1 cent piece,
- It is blank on one side, and
- The blank side is "silver" in colour,
Then it seems obvious what has happened: someone has taken an ordinary 1 cent piece, and ground down one side of it with a dremel or similar tool, until it is flat. Doing this will scrape away the copper plating on that side, revealing the zinc core underneath. And zinc, when it is still shiny and fresh, is silvery in colour.
So, it is not a mint error, or anything other than a "damaged coin". Sorry.
If you want confirmation, find yourself a digital scale that can weigh tot he nearest 0.01 grams, and weigh it. If my hypothesis is correct, then it should weigh considerably less than a regular cent.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis