If its something important you probably want a fireproof container which could be in a box labeled "ornaments".I've read in a few places that stashing things away so as to not be quite so visible while 'out in the open' is one way to hide things. Someone suggested putting them in the garage with a bunch of other boxes and labeling them "Christmas ornaments" or "photos of Grandpa". I'm wondering what boxes you wouldn't bother to look in if you were in a hurry. If you had unlimited time, you would obviously look in them all (or tip them all out) , but given a very short time what would you choose to ignore ...for now.
You want to be sure its not something that will get thrown out by accident.