I used a heat gun to see how each fabric was changed by the heat. All of the fabrics (except one my friend brought along) contained polyester. I have a book called "Raising the Surface with Machine Embroidery" by Maggie Grey that contained a lot of ideas about how to manipulate fabric with heat.
Before I start, let me be clear that if you choose to heat fabric in any way, do it outside. The fumes are harmful to your health! I began the afternoon (outside in my garage) with a suggestion from the book--a chiffon sandwich. I made a sandwich consisting of two pieces of gray polyester chiffon, foil, and fusible web. (I used Heat and Bond Light since that is what I had on hand.) I covered my ironing board with parchment paper and put one of the chiffon pieces on top. I then pressed the fusible webbing onto that piece. I removed the paper backing from the fusible; and while it was still warm, I put some foil on it (shiny side up). I rubbed the foil with the edge of a blunt knife till I had as much color as I wanted, removed the clear top sheet of the foil, and ironed the other piece of chiffon on top of the fusible. (I covered the chiffon with parchment paper before ironing.) This is what that looked like. (The picture turned out darker than the actual fabric.)