Willem van Aelst is built on dark foundations, with values clustered toward shadow. The dominant temperature is warm, with earth tones and fire-hues setting the emotional key. Chroma hovers near zero; colour declares itself through subtle shifts in hue rather than outright saturation. 45.6% of the palette belongs to #1A1614, a concentration that makes it the unmistakable visual centre. The saturated accent, #624827, registers at 5.6% - sparse enough to feel like a deliberate surprise. A value spread of 59 units gives the palette both depth and air - shadows are genuinely dark, lights genuinely light. Together these qualities place Willem van Aelst firmly in the tonal tradition - concerned with mood and atmosphere rather than chromatic display. Palette 4 sits within the larger chromatic argument that Willem van Aelst's complete body of work advances.