To embed this, cut and paste the following html into your web page:
8" by 8" test palette of hue triangles, in 5 subdivisions of the full nominal colour range, arranged in a square diamonds format. The colour rainbow can be traversed as if outlining the semi-regular octagon and square grid. The gaps between pure colours (RGB and CMY) are covered by hues which are simple fractions: half, thirds, quarters, fifths and some sixths.