I'm absolutely certain that this is going to make a few, or perhaps many brides scream a little. But I think I'll be able to make a good point if you hear me out. Your gift to the members of your wedding party is intended to be a thank you gift in appreciation for their friendship & support through your wedding planning, as well as a thank you for the financial considerations they've made in being a part of your celebration. Because your thank you is sincere, your gift should be as well. This gift should not be about the wedding. Rather, it should be a gift truly meant for each person. So tell me how purchasing all your bridesmaids matching jewelry, that you think compliments the dresses you've chosen for them and that you feel embraces the look of your wedding (again making it about your wedding)is a sincere thanks to each individual? Here's my thought. Buy each member a gift meant specifically for their personality and tastes. If possible, buy a gift that is something that you know they would love but never purchase for themselves.
Don't get me wrong; I adore jewelry as a thank you gift. Jewelry is exciting to give and receive. So for goodness sakes, give jewelry she'll want to wear again. And do what you can to make it personal so that each time your dear friend & bridesmaid wears it she'll think of that great time in your lives.