I made some prefelts the other day and cut out several circles to include in this lively design. I used only kool-aid dyed merino wool and silk in the piece. The kool-aid bled a bit during the hot water stages (meaning the dye was not completely "colorfast") — the bleeding came mostly from the silk scarf, I think. However, by the time I did the final warm-water vinegar rinse, the water was running clear. Regarding the prefelts: I loved working with the prefelt cutouts and am surprised how well the cut pieces retained their shape during the felting process!