Tertiary color if they exist at all, though indigo and scarlet are standard for blue–violet and red–vermilion. In another sense, a tertiary color is obtained by mixing secondary-colored pigments. These three colors are russet (orange–purple), slate (purple–green), and citron (green–orange), with the corresponding three quaternary colors plum (russet–slate), sage (slate–citron), buff (citron–russet) (with olive sometimes used for either slate or citron). Beyond that are shades of grey (blue grey and brown greys), which approach but never quite reach black. The RYB color terminology outlined above and in the color samples shown below is ultimately derived from the 1835 book "Chromatography", an analysis
HSL and HSV the mixture of those paints with varying amounts of black or white paint. The HSL model attempts to resemble more perceptual color models such as the natural color system (NCS) or Munsell color system, placing fully saturated colors around a circle at a lightness value of , where a lightness value of 0 or 1 is fully black or white, respectively. HSL and HSV are both cylindrical geometries (), with hue, their angular dimension, starting at the red primary at 0°, passing through the green primary at 120° and the blue primary at 240°, and then wrapping back to red