I spent an obscenely long amount of time making this and trying to figure out how to superimpose the image of the knot into the seat. I tried a few different methods, including importing the drawing version from illustrator and creating a separate object from that, using extrusion and boolean difference techniques, but in the end the method that worked best was importing the image and using it as a texture, pasted straight onto the surface.
I used a walnut veneer as a base, as I like the way the darker wood looks with the metal as a contrast, but I also played around with a few other types of wood, and other colours. For example, using a different colour for the seat itself, or using a different material for the pattern. I quite like the idea of using an iridescent sheen on the pattern, as that would make it more eye catching.