Thanks for the instructions! I would not have guessed foam; it has so much great rocky texture. I've always been a little afraid to try foam (because of the durability issue), but with those kind of results I may have to risk it.
Thanks for the kind words! I've been meaning to start posting for a while and finally had a bunch of spare time. The wings are one of my first attempts at airbrushing and I'm very happy with how they turned out.