Colour
- Sensing body part: Eyes. The lens and cornea focus light to fall on a surface of rods and cones, the pattern of which is sent to the brain as electrical impulses.
- Element: Primary colour
- Medium: Colourants (usually ink) on a white surface, or light on a black surface
- Types of element: For colourants, cyan (reflected blue and green light), magenta (reflected red and blue light) and yellow (reflected green and red light) (practical implementations also use black), although the fine arts has traditionally used blue, red and yellow (which alone cannot theoretically produce black). For light, red (long-wavelength visible light), green (mid-wavelength visible light) and blue (short-wavelength visible light).