I'm assuming the chain is too. It is the one that came with it. I think it's 18 inches. And it has little rings on the end to make it adjustable length.
I see the extra link on the chain, that is the first time I've seen a chain done this way! Lol well the stamp is on the clasp, so it could be its just the clasp but still strange if the chain wouldn't be also since everything else is. It's nice either way and the only reason I asked is because I'm allergic to costume jewelry so it has to be real gold or 925 SS.