n.
Drawing medium consisting of fragile, finger-size crayons called pastels, made of powdered pigments combined with a minimum of nongreasy binder (usually gum tragacanth or, from the mid-20th century, methyl cellulose).
Because pigment applied with pastel does not change in colour value, the final effect can be seen immediately. Pastel remains on the surface of the paper and thus can be easily obliterated unless protected by glass or a fixative spray of glue size or gum solution. When pastel is applied in short strokes or linearly, it is usually classed as drawing; when it is rubbed, smeared, and blended to achieve painterly effects, it is often regarded as a painting medium.