You may have found more than you think!
The unclipped penny looks like a possible Indian Head cent. Be gentle cleaning it. One method which has worked for others here is to heat up a small amount of hydrogen peroxide for 40 seconds in a microwave-safe container, then allowing the penny to sit it it for 20 minutes. Next, using a small toothpick, try rubbing the toothpick over the date-segment of the coin only. You should be able to obtain a clear date within 4-5 minutes of careful cleaning. Try dipping the toothpick often to keep the wood wet or at least damp, and don't press down hard.
Do show us what the coin looks like afterwards. And use your own judgement on whether you want to spend the time cleaning the entire coin ... or not.
Either way, welcome to TNet, and thanks for sharing!