Worth repeating!
Also, what about sunblock, perfume etc that may have come in contact with your necklace?
I'd still make the trip back (or mail it back) and get a replacement.
Nope... Nothing at all could have came in contact w/ it. I purposely never spray perfume on my neck so I don't ruin my necklaces... No lotion. No sunblock. Nothing.
Also to answer Ratnapur's question... I remember it WAS hot out when I wore the necklace, but I've worn other silver jewelry those days and everything else was perfectly fine. Also, I've worn my other Tiffany necklaces in VERY sweaty conditions, such as the beach, working out, and hiking and never had any problems whatsoever. To me, something had to be defective w the necklace for it to be tarnished this bad. I'll just call Tiffany this weekend and update you guys with the outcome.