I recently got back from the store. I bought two dummy rings for my character. One of them, I broke down, and it is now essentially just a band. I have colored it black because I could.
The other is made to look like silver, and had a very prominent fake gem in it. Large. I colored this jet black as well, to give it an oynx look. I am not sure which I should try out. On the one hand, (literally), I think a King's son, as well as the Duke of Brittany would have a very prominent, impressive ring. But it is a bit bulky, though nothing I cannot handle.
On the other hand, this Prince is Geoffrey, and I can see him being less concerned with bulk and such. The smaller, simpler, (yet black) metal band actually resembles the sort of character I think Geoff can be. Plus it is lighter on the hand. (not by much, but it is.) I think it would be easier to play with, and that was, in theory, the purpose of having a ring.
I think tonight I will try both. Maybe see if the director has a preference. I want to have a decision tonight, though. I want to have what i am going to use in place as early as possible.