Silver and Other Established Rules

Can vampires wear silver jewelry? Probably not, but I love the look, and prefer silver to gold. I think my new characters would look good in silver, but... well they're vampires and that kind of kills the idea. Unless I bend the rules. I mean if Twilight vampires can shimmer instead of burn, maybe my vamps can wear silver as long as it is just jewelry. It makes me wonder how far we can bend the established "rules" for certain types of characters. If you do it, of course you have to explain it so readers aren't thrown off by it. But is there a limit to how far you can go before even an explanation won't work?