Single pigment colours, are those acrylic, water, gouache, glaze and oil colours consisting of a single pigment. They may be recognized by the fact that the contents on the tube only list one pigment, e.g. Vanadium Yellow deep (PY 184), Ultramarine Blue (PB 29), Ruby (PR 264), or Neutral Grey (PG 7). The great advantage of single pigment colours, as opposed to mixed pigment colours, is that they permit very simple and easily reproducible mixtures. Mixed pigment colours, on the other hand, consist of two to five pigments of unspecified quantities, e.g. Cobalt Blue (PB 28 / PB 60), or Prussian Blue (PB 60 / PB 15:1 / PBk 7), which may cause surprising interactions when they are used for glazes or further mixing.
The Soviet infantryman pictured in the center was glazed with the single pigment colour PRIMAcryl 13.684 »Natural Burnt Umber«. The soldier on the right has received a glaze of Lukas Studio 311 »Burnt Umber« which developed an unanticipated reddish cast.
In principle, any desired tint, tone, or shade may be mixed from single pigment colours, for example if a colour perceived in nature or seen in a painting guide is to be used in a diorama or applied to a miniature.