Arthur Rackham distributes its values across the middle register, creating harmony without high contrast. The dominant temperature is warm, with earth tones and fire-hues setting the emotional key. Saturation is deliberately withheld - the beauty here lies in the near-monochromatic gradations rather than colour difference. The saturated accent, #B9885E, registers at 4.5% - sparse enough to feel like a deliberate surprise. A value spread of 60 units gives the palette both depth and air - shadows are genuinely dark, lights genuinely light. Palette 13 sits within the larger chromatic argument that Arthur Rackham's complete body of work advances.