The colour combination - the palette of an artist - mostly follows esthetical guidelines - and also - the practical use. Manufacturers of artists' colours have to consider and follow a didactical purpose of the colour selection for best possible mixing results. Other important factors are transparency and lightfastness. When composing the standard boxes - those are the long metal sets - the lightfastness and transparency of the selection are as important as the coloristical choice and the mixing options of the included colours.
For more information, please download the PDF: HORADAM® water colours: concept of painting sets