Gustave-Claude-Etienne Courtois distributes its values across the middle register, creating harmony without high contrast. Warm hues command this palette; Gustave-Claude-Etienne Courtois favours the reds, oranges, and yellows of firelight and earth. The absence of saturated colour is itself an expressive choice: this is a palette of restraint and atmosphere. At 3.8%, #B32E1E carries the palette's sharpest chromatic charge: an accent that earns its place precisely because it is withheld. From deepest dark to palest light, the palette traverses 73 units of the value scale - a span that creates natural depth. Palette 4 sits within the larger chromatic argument that Gustave-Claude-Etienne Courtois's complete body of work advances.