A dye-free nail varnish that is used alone or with a stamp to generate a colored coating under incident white light is presented. The nail varnish includes photonic particles and/or block copolymers that can self-assemble to provide a structurally colored coating. The stamp presents a pattern of repeating nanostructures that can be transferred by imprinting the stamp on a coating of a dye-free nail varnish, thereby providing a structurally colored nail varnish coating. Thus, the nail varnish and stamp, independently or together, provide structurally colored coatings without the use of dyes or pigments.