Jean Dubuffet is high in key: pale, luminous, and filled with optical air. Jean Dubuffet builds on cool foundations: the palette favours the blue-cyan-green arc. Chroma hovers near zero; colour declares itself through subtle shifts in hue rather than outright saturation. #F0E5BF at 19.0% is both the most chromatic and one of the largest colours in the palette - chroma as mass rather than as highlight. The full value range is 76 units: broad enough to build convincing three-dimensional form. High luminosity and cool temperature suggest the plein-air condition: unfiltered daylight and open sky. In the context of Jean Dubuffet's full range of palettes, group 1 represents one movement in an ongoing chromatic dialogue.