Pastel is one of the purest forms of pigment that can be applied to a painting surface. Pastels are generally bound with resin or gum. If the same pigments were bound with oil, they would be oil paints. Because pastels have no oils, they do not yellow or breakdown as oil paintings can over centuries.
The use of dry pigments as used in rendering images can be observed in cave dwellings, long before the written language was created. The present form of pastels was established in the 16th to 18th centuries. During this time, artists used pastels to color their sketches as studies for larger oil paintings. By the end of the 17th century, pastels were growing as an autonomous form of art.
Pastels
