Tonalism as a style is partly defined by its colour: this palette makes that definition concrete. The value structure of Tonalism is mid-key: quiet, controlled, and cohesive. Blues and teal-greys govern the palette, lending it an aquatic or atmospheric quality. Muted throughout, the palette achieves its effects through value and temperature rather than chromatic force. The highest-chroma note - #9C6237 - appears at just 5.3%, deployed as a precision accent against the quieter ground. The full value range is 63 units: broad enough to build convincing three-dimensional form. The mid-to-high key, cool bias, and moderate chroma point to outdoor observation - sky and diffused daylight as the dominant light source. Any work aspiring to the Tonalism sensibility would find reliable footing in these values.