Gold stolen from rings?!

Also when I was having my engagement ring sized I also had my wedding band sized so I am worried that it will have the white gold stolen out of it as well. I still haven't told my FH and don't know how or when to tell him.

It might not be that gold was stolen from your rings. White gold rings are supposed to be dipped in a rhodium finish that keeps them from tarnishing. I suspect that maybe your rings were not dipped in this finish. I would contact the jeweler you purchased them from and ask if the rings were dipped in the rhodium finish. If not, ask them if they would fix the tarnish on your rings and then get them dipped in the rhodium. I hope this is what is wrong with your ring instead of the gold being stolen!

The thing that makes me think the gold was stolen is because only half of the ring has tarnished where the ring was re-sized. The rest of the ring is fine!

It's not likely that the gold was stolen from your rings. White gold usually has a layer of Rhodium to bring out the brightness. This may need to be done periodically and especially after sizing up... it sounds as though the jeweler may have forgotten this step. Usually white gold rings will have a very, very faint yellow gold tint after years because it is gold. Alloys like nickel are added to give your ring the white appearance but gold can't be removed. Take your rings to an independent jeweler to have them inspected before you panic.

Also the area that is tarnished isn't yellow its almost black.

If it is black, that makes me think you just need to clean it. I had a white gold class ring years ago that turned black from wear and tear. Simply getting a jewelry cleaner and soaking it got the black grime off the ring.

Another thing, if your ring tarnishes, I'm pretty sure the only thing it does is look scratched. I'm pretty sure tarnishing doesn't cause the ring to become discolored.

Tarnish causes discoloration that looks bronze to almost black dependent on how long you have gone with out cleaning and is found in silver. It is a layer of corrosion. I am probably not explaining all of this very well and if I had a decent camera I would just take a picture of it. Anyways, that being said I get my ring cleaned on a fairly regular basis and last had it cleaned about a month ago. Just after I had it sized.

Ok well then I'm almost positive that it just didn't get the rhodium finish. I'd ask your jeweler and if it hasn't, you should be able to send it off to get it repolished and dipped in the rhodium.