Algodoo

If I understand Einstein's General Theory of Relativity, gravity is not made up of "gravitons" or any other such particles. Gravity is simply the result of curved space-time, and space-time becomes curved by massive objects. The more mass an object has, the more space-time gets curved close to the massive object. That curving of space-time is what we witness as gravity. No gravitons necessary!

I believe they're called baryons

"So there is no way of knowing which is which. Unless they come closer."
Actually, even then, there still is no way to tell. It's possible to compare two particles, to tell if they are identical or opposite, but you can't say with certainty if either is matter or antimatter.