How to Care for a Pastel Painting
To preserve the brilliant colors, pastels are not sprayed with any fixative on the final layer. (Fixatives will darken the painting.) This means that the painting can be smeared if the unframed painting is not handled carefully. Let your framer know that this is a pastel and to be gentle with it. Also, if the framed painting is not handled gently, small particles of pastel can fall from the paper and stick to the inside of the glass or mat. These particles are easily removed by taking off the frame -- but doing so carefully! -- and using a small kneaded rubber eraser on the mat or a lint-free cloth on the glass. Otherwise, the painting is care-free. The colors are permanent; there are no oils to darken them as is the case with oil paintings, and the colors will not fade as with watercolors.
Pastel is a dry medium in a stick form, consisting of powdered pigments held together with a binder. Painting with pastels, therefore, is as close as one can get to painting with pure pigment. Some pastel contains a small amount of chalk but is not just chalk.Rosalba Carriera was the first artist to explore painting with pastel. There have been a multitude of famous artists since who have used pastel. Delacroix, Millet, Manet, Renoir, Whistler, and Cassatt are a few. The French Impressionist, Edgar Degas was the most prolific user of pastel.
In and out of style in the last four centuries, pastels are now enjoying a modern-day resurgence of popularity, due to their intense colors and "immediate" handling. A versatile and "forgiving" medium, soft pastels are adaptive to the fast pace of today's lifestyles.
If you would like more information on the medium pastel go here.