The Munsell colour system is no doubt useful for capturing and describing colour information from soils (and from many other features). It is also designed to be appropriate for the human visual system, allowing relatively easy discrimination between different values of Hue, Chroma and Value. However, the fact that it is composed of a colour ‘wheel’, in which Hue values move from R (red) through other colours and back to R, makes it difficult to provide information on how ‘far’
colours are from one another in the colour space. In addition, the Hue categories are just that — categories. In order to provide a numerica description of colour, these categories must be converted to some valuation.