Okay, so there's the whole something old, something new, something borrowed, something new (sixpence in your shoe) deal, right?
As my something borrowed, my mom has a necklace that belonged to my gram that she always, always wore. It's nothing fancy, just a gold chain with a medallion of Mary (the religious, Catholic-y one).
I know you can pin stuff like this inside your dress, but part of me just wants to wrap it around my wrist like a bracelet. My rings are platinum, the detailing on my sash is silver and my earrings will almost certainly be silver.
Here's a poll: Mixing a gold bracelet (although a slim one) with silver jewelry: Do or Don't.