John Boultbee sits in the centre of the value range, lending the palette a sense of even, sustained light. Cool hues prevail: blues, greens, and greys anchor the palette's emotional temperature. Chroma is kept low across all colours, producing the soft, enveloping quality that characterises tonal painting. The most saturated colour, #451D0F, is reserved to 3.3% of the surface, where it acts as a focal punctuation. A value spread of 61 units gives the palette both depth and air - shadows are genuinely dark, lights genuinely light. The palette has the character of outdoor light: cool, mid-bright, with colour rendered faithfully rather than expressively. In the context of John Boultbee's full range of palettes, group 6 represents one movement in an ongoing chromatic dialogue.