How did you contact Carnival? You will probably be required to mail them a copy of your store receipt and a description of what happened to your item (where and how it broke). It probably won't do you much good to e-mail or call. You may also need to mail in a copy of the guaranteed stores you got on your cruise. Start with your travel agent first.
What store did you buy it from ? Was it a store that Carnival had listed in their shopper's guide? Do you have a business card from the store ? Last year, when we got home from our cruise, a pink sapphire was missing from a ring we bought at Goodmark. I will ask my mom how she took care of it. Goodmark took care of it with no problem.
Nieuw Amsterdam 12/92
Soveiegn of the Seas 8/03
It will probably take quite some time to hear back from Carnival, advising you what to do, what kind of paperwork to send in to them, mailing the piece of jewellry to the store for repair, and waiting for the store to return the item. Years ago in St. Maarten, I bought a pretty amethyst ring with one large and several smallish stones in it at AH RIISE. Right after I got home, one of the smaller stones fell out. I mailed back to the store on my own (because I got the store guarantee). The replaced the stone and mailed it back pretty quickly. Sure enough, it fell out again. At that point, I just took it to a local jeweller who matched the color and r eplaced the stone. It cost about as much as the postage back to St. Maarten would have cost. No problem at all since then, and I wear that ring a lot!