you can see here and which is the Ocean convertible necklace and tiara from Van Cleef & Arpels). This piece is called the Diamond Foam Tiara, and you can read more about it here.
UPDATE: Here is Armani's sketch for the evening gown
What did you think of the bridal party's evening attire?
Photos: Newscom/vg.no/Getty Images/Daylife/Vogue