In terms of art, Pigment refers to a dry natural substance, usually in a fine powdered form, which is added to a binder (or vehicle) in order to produce coloured materials such as paint, dyes and inks. Pigment colours can be found in natural sources or can be synthetically created with chemicals. Natural pigments such as ochres and iron oxides have existed since prehistoric times along with Biological pigments which are harvested from insects and molluscs. There are also mineral pigments found in the earth, stones and clay; for example, the semi-precious stone lapis lazuli which is used to produce the natural blue pigment ultramarine. Industrial and scientific revolutions have, since, allowed the production of synthetic pigments, drastically widening the range of colour available to artists and manufacturers. Many famous historical pigments have now been replaced by synthetic pigments which are more consistent although they retain their historical names.
The harder it is to manufacture or process a pigment, the more expensive it will be and this will be reflected in the price of the paint colour the pigment produces.