The 12 part colour wheel below is based on the three primary colours ( Red, Yellow and Blue ) placed evenly around a circle. Between the three primaries are the secondary colours (Green, Orange and Violet) which are mixtures of the two primaries they sit between. The tertiary colours fall between each primary and secondary colour. Between yellow and orange, for example, is yellow orange, between blue and violet is blue violet and so on.
All these colours around the outside of the colour wheel are called saturated colours. They contain no black, no white and none of their complementary or opposite colour. NB. Some books will refer to tertiary colours as a mixture of the three primaries and only break the colour wheel into six colours (primaries and secondaries). We prefer the theory based on Johannes Itten's 12 part colour wheel, as it offers a much better understanding of the interaction of colours.
Compound colours are colours containing a mixture of the three primaries. All the browns, khakis and earth colours are compound colours.
In the illustration below the compound mixtures between red and green are shown, as are tints and shades of the colour wheel. Tints are made by adding white to a colour, shades are made by adding black
Imagine a colour wheel filled in with all the compound mixtures between all
the complementary colours. If this colour wheel is placed in the middle of
a cylinder with progressively darker shades of all those colours below and
progressively lighter tints above, the cylinder would contain every possible
colour!
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