A relationship between assessed color differences and assessed components of colors is presented. The perceptual difference between colors j and k is converted to a lightness difference of two Mansell grays, V-A and V-B, and d(jk) = \V-A - V-B\. Scaled values of principal hue components of a color xi(alpha) (H\V/C), alpha = R, Y, G, and B, are read front charts based on assessments of observers. Previous charts (Color Research and Application, 1999, 24, 266-279) are enlarged and extended. A linear combination of DeltaV = \V-j - V-k\ and Delta(ξ) over bar (alpha) = \(ξ) over bar (alpha)(H-j\V-j/C-j) - (ξ) over bar (alpha)(H-k\V-k/C-k)\, (d) over tilde (jk), is the best to predict d(jk). The root-mean-squares of (d(jk) - (d) over tilde (jk)) is 0.34 V, about one third of the lightness difference from V to V + 1 on the Munsell Value Scale.