blckshdwdragon thinks hue has something to do with gray and black

Um, hue is part of the spectrum. Ie. a red hue, a magenta hue.

Quoted from websters:
Main Entry: hue
Pronunciation: 'hyü
Function: noun
Etymology: Middle English hewe, from Old English hIw; akin to Old Norse hy plant down, Gothic hiwi form
1 : COMPLEXION, ASPECT <political parties of every hue -- Louis Wasserman>
2 a : COLOR b : gradation of color c : the attribute of colors that permits them to be classed as red, yellow, green, blue, or an intermediate between any contiguous pair of these colors -- compare BRIGHTNESS 2, LIGHTNESS 2, SATURATION 4

Black is decomposed of ALL of the colors. Hence hue, or tone are appropriate.