 The tertiary color on the HSV color wheel (also known as the ) precisely halfway between blue and magenta is called color wheel violet.This tone of violet—an approximation of the color violet at about 417 nanometers as plotted on the CIE chromaticity diagram—is shown at right.This tone of violet is actually somewhat toward indigo assuming indigo is accepted as a separate spectrum color, usually quoted as having a range of from about 420 to 450 nanometers.