Yay! I went and picked up my Bridesmaid's dresses today

I let them pick out their own dresses but they are all the same color - Lapis (dark purple) from David's Bridal. Here are my sisters modeling their dresses and holding up the other three.
Now that I have all of the dresses, I am trying to figure out what type of jewelry to get them (for their BM presents). I am kind of leaning towards earrings and bracelets. Since all of the necklines are different, I think that a necklace would be hard to find that would look good with all of them.
Any thoughts or suggestions?