In the mutant stories, the metal band worn on the wrist is used for ID purposes but it's way more than that. There is something about the band (I haven't figured out quite yet) that blocks the lower forms of mutations, keeping them from being of use to the person. It doesn't work on someone of Noah's abilities, but it does work for Dominic (an unregistered one) and in the YA one, Ephram has one. They aren't intricate or anything, with only a couple of markings so the agency can tell if they have been taken off. And they do come off. There was a bit question over why the government would require mutants to wear something that could be removed and I think I figured out an answer for why young people who are still growing would get ones that can come off. ;-)
The slave collar is one that is iconic for the Master/slave relationship and I have a couple M/s stories that I've done for contest and such, but there is also a novel that is going to involve the slave collar. The main character is a magic wielder (considered closer to a demon in some way and hunted by non-magic people) and the only way for him to survive and not be hunted is to be owned. I have only done one scene for this story so far but am looking forward to it. May also look for some other ownership jewelry to use besides the collar some day.
This type of jewelry can also have many different uses. There are family rings, engagement rings, promise rings and so many more. There is one story in particular that uses rings (and it's for male characters, hehe). In this one that I call Sekrit novel (yes this is one of the first times I've share any details really) the main character has a few rings and if he gives them to people it is a sign of their connection and of devotion. And if he wears one of their rings, it has a special bond meaning as well. I am still working on that one, or kind of sort of umm I haven't written in months in it but will soon I hope.
Do you use jewelry in any stories?
How do you use jewelry?