I used dyed and felted wool blanket for the backing for these:
Scraps of sari silk and wool tops (roving). To keep the very fine layer of wool tops in place, I put a piece of net (tulle) over the top and tacked it all down by needle punching lightly first, then removed the net and needle punched both surfaces.
Scraps of sari silk, thicker shot silk, wool tops and some tangled silk threads that I bought in the market once because I knew they would come in useful for something!
This is the back of the previous piece. I needle punched more pieces of silk to the back of the piece, to get a lighter effect on the front.