Increasing strength of color
Chroma refers to the relative purity or strength of the spectral color. Chroma runs from 0 (neutral gray) to 8 (highest strength of color found in soils).
Chroma increases to the right across the Munsell page. All chips in a column have equal chroma.
Zero-chroma chips have no color, they are neutral gray. Often they are simply given a hue designation N (neutral).