U. Hawaii's formal robes were in emerald green with white arm stripes, and I wore them when I got my MBA at Cornell, because I didn't walk in Hawaii. Cornell of course has deep crimson/scarlet/red with black arm stripes, so all morning it looked like I was a photographic negative of everyone else. I still get comments about that to this day. The robes are expensive, but at least you have a ready costume for emergencies!