At the time I made The Knot-Shop Man books, I did not have a coin featuring two six-fingered dragons with a hole in the middle (those... turned up later). So the cover is actually a jam-jar lid shot on four different arrangements (four covers for four books) of rope from a downward-facing tripodded camera [photographer: Mark Callaghan]). Then René's line art of dragons and a lot of Photoshop to fake it into metal. Example of “Earth” cover to show the end result.