The quality of a color that describes its amount of saturation, or strength, particularly according to the Munsell color space model. Chroma is similar to saturation, though in the Munsell color space it relates more to the amount of colorant present. It is in this definition of chroma that Munsell's color model differs substantially from all previous proposals. While the circle of hues includes all conceivable hues, and while the value axis is all-inclusive, Munsell realized that new colorants were constantly devised and chroma is therefore open-ended. See also Saturation.