This was a gift from my dad a long while ago, so I'm going to say they are NOT real diamonds. As far as them being stamped or not, I'm new at this so I'm not sure what that means... Sorry!
Having a stamp shows its real silver(925) or gold (10kt,14kt) it will be on the back or clasp of the piece of jewerly. Just an fyi for you cause you will get asked alot