PASTELS ARE STICKS OF PIGMENT made by mixing ground pigment with chalk and a binding medium, such as gum arabic. They vary in hardness depending on the proportion of the binding
medium to the chalk. Soft pastel—the most common form of pastel—contains just enough binding medium to hold the pigment in stick form. Pastels can be applied directly to any support (surface) with sufficient tooth (texture). When a pastel is drawn over a textured surface, the pigment crumbles
and lodges in the fibers of the support. Pastel marks have a particular soft, matte quality and are suitable for techniques such as blending, scumbling, and feathering. Blending is a technique of rubbing and fusing two or more colors on the support using fingers or various tools such as tortillons
(paper stumps), soft hair brushes, putty erasers, and soft bread. Scumbling is a technique of building up layers of pastel colors. The side or blunted tip of a soft pastel is lightly drawn over an underpainted area so that patches of the color beneath show through. Feathering is a technique of applying parallel strokes of color with the point of a pastel, usually over an existing layer of pastel color. A thin spray of fixative can be applied— using a mouth diffuser or aerosol spray fixative—to a finished pastel painting, or in between layers of color, to prevent smudging.
