Last night I was bored so I looked through my writing journal (I have a journal that I uses to jot down ideas, characters, maybe even a page or two of a scene for future stories) and I found that I had 2 story ideas with the same theme: An unremovable necklace. Story 1: girl has a simple necklace that has a rune on it. She's had it all of her life. No blade can cut it. A magical artifact dealer wants it but cant remove it. She informs him (after he say's he'll just chop her head off and take the necklace) that if she dies, the rune is rendered useless, so he takes her with him so his brother/business partner can figure out what to do about it/her. Story 2: girl has a necklace that tightens whenever she uses magic. She doesn't know who put the "collar" on her, and doesn't know about her magic. all she knows is that when she does this one thing, the necklace gets tighter. So she goes on a quest to figure out who put the collar on her and how to take it off (I actually made a character chart and plot chart for this one in my notes) I don't know what I was going through at that time (both times, I guess, because the dates are far apart), but now I'm thinking if I decide to move forward with them sometime in the future, I'd have to pick one of the other. Not both!
I like story two as it would add more tension, where story one seems like it would be more frustration. ETA There could be a situation she could save a life, but one more trick will cause her to give up her life.
I see absolutely no reason why these two plot-lines are mutually exclusive? An irremovable necklace that the rune dealer wants but gets tighter if she uses magic - loads of tension in there! Get her into a situation where she needs to use magic but is risking her own life by doing so and the damn thing can't be taken off to do the magic because - well it can't and would become useless
You have two plots and no theme is what you actually have. What do you want to say? If you know that then you have a theme and then you can choose which plot will say it best.
I say do it, and power to you. There's nothing wrong with magic necklaces and don't worry about being the writer associated with magic necklaces, rather, think of the merchandising potential for toys not to mention endorsement deals with diamond cutters and high end jewelry makers. If I can write about magic guitar amps and guitars, why not?
I actually like the idea of both plots as one, especially how Hammer put it. Maybe a powerful relative she never expected put the cursed collar on her neck? Maybe she finds out there is secret key that can unlock the collar? Definitely interesting plot idea though!
I like both. I'd say write both. They will deal differently with the issue. In fact, thinking ahead, you could write several more stories involving necklaces that are not removable, and see where they would lead you. Then pull all the stories together into one volume? The notion of a necklace as a collar (like a dog collar) that restricts a person, and can't be removed is an interesting one. Who controls that collar? Is there any instance where it can be removed? Would that feel like freedom or loss? Does the wearer break away, or does the controller let the wearer go? With or without conditions imposed? There is also the notion of a necklace carrying something precious that the wearer can't or definitely doesn't want to lose. (Think Frodo and the Ring.) There is the notion of a necklace as decoration which the wearer is proud of, or as a status symbol, or as an identity symbol, or as a memento that means the world to the wearer. Lots to play with here—including the concept of 'not removable.' That's not necessarily always magic. It can simply be what the wearer sees as necessary to themselves, for some reason. I'm not a fan of story prompts, but that might be a good one. A necklace that can't be removed.