Chalk pastels are a type of art material used to create color works of art. A chalk pastel is created by mixing pure colored pigments with a substance such as gum arabic that binds it together. Chalk is added to the pastel to soften the color, create a variation from the pure tone and help transfer the pigment to the surface being drawn on. The pigment contained in a chalk pastel is present in the highest concentration of any drawing medium.
Many artists employ chalk pastel to create small studies that can be used for larger paintings in a different medium. This is because of the very immediate nature of working with chalk pastel. They are easy to use, have good color depth and can be blended without effort. Some artists produce entire compositions with chalk pastel.
Using chalk pastels is relatively easy compared to some other mediums that require mixing, thinners or other special supplies. The primary technical aspect of using chalk pastels is the amount of dust produced. Each stroke of a pastel will create a significant amount of pigmented dust. This dust collects quickly and can be hard to remove from clothing and even other areas of the drawing surface. Using an easel can help to reduce the amount of dust that must be dealt with.
The type of paper used is important when working with chalk pastels. The pastels rely on the roughness of the paper to evenly distribute their pigment. Smooth surfaces, such as hot-pressed art board or Bristol board, might not be suitable because the pigment will not be applied evenly. Rough surfaces such as cold-pressed boards or watercolor papers are preferable, especially when they have a smaller grain. Softly colored papers are commonly used for pastel artwork, specifically light sepia and gray tones.
Completed chalk pastel artwork is incredibly vulnerable to smudging and other hazards. Even the act of framing a pastel piece can destroy parts of the painting. For this reason, spray fixatives are a crucial element of using chalk pastel. The fixatives will create a binding coat on the pastels and seal them in place. Although the pastels might still smudge even with the fixative, it will be much more difficult to do so.
Spray fixatives can be used during the creation process, as well. They can be used to create different layers of chalk pastel to serve as an undercoating that does not interact with the next layer. This process takes time, however, because the fixative must dry completely before it is safe to apply more pastel on top of it.