Jérôme-Martin Langlois is built on dark foundations, with values clustered toward shadow. Yellow, ochre, sienna: warm hues that Jérôme-Martin Langlois deploys as the palette's primary energy. Saturation is deliberately withheld - the beauty here lies in the near-monochromatic gradations rather than colour difference. At 30.0%, #130B07 functions less as a colour accent and more as a complete atmospheric environment. #7E390F delivers the chromatic peak at only 4.6% - a small shot of colour with outsized visual impact. The value range spans 59 units across the palette, providing the full gamut from deep shadow to near-white and ensuring clear tonal hierarchy. Together these qualities place Jérôme-Martin Langlois firmly in the tonal tradition - concerned with mood and atmosphere rather than chromatic display. In the context of Jérôme-Martin Langlois's full range of palettes, group 4 represents one movement in an ongoing chromatic dialogue.