In the last part of this series about the advantages of using a limited palette, we look at the staining properties of watercolour pigments. By its nature watercolour is a staining medium, laid in thin films over a paper surface made of cotton or pulp and set in place by the gum Arabic binder. Most pigments seep into the fibres of the paper, staining the fabric to a greater or lesser extent, while others sit on or between the fibres and can therefore be lifted off by varying degrees, even when the paint is dry.
The level of staining depends on the pigment, not on the transparency or opacity of a colour, and as the information is relevant to the artist, manufacturers mark it on the label of the tube or pan with a triangular symbol. Since brands formulate their colours from their own pigment recipes, the specific colour names (mainly Schmincke) mentioned in this article may not have exactly the same properties in other ranges.
Staining and semi-staining pigments
Most Artists’ watercolours
