Post this last year, figured I'd give it another shot. I've seen this type of sconce used in movie theaters. It uses a type of monochromatic glass I believe. I want to use them for a prop display room.
I'm weird in the fact that I even noticed the lights at the theater I used to go to. It was a AMC and they actually had several panels of glass. One thing I noticed is that the side I could see (bottom) the glass appeared to be mirrored, almost holographic to where they would reflect one color and pass another. As a result it almost appears that the glass panels are emitting light rather than reflecting the white source light. Very cool effect. Gels or stained glass wouldn't have the same effect.
Thanks for the tip on Edmonds, I'll see if I can get something from them. Guess I could also check with some glass speciality shops as well.