You should let the brides maids think about their own jewerly and what they want to wear, they will feel part of your occassion and will feel that they contributed something toyour day. let them feel cormfortable and heppy being a part of your day by having them get what they prefer. i tried it myself and it worked.

Each of them has some thing they like, it would be nice to choose things they individually treasure and would remember you for.