Pastel
Pastels have been used as a serious art medium for centuries. They have been used by notable old masters such as Jean Baptiste Simeon Chardin, Edgar Degas, and Mary Cassatt as well as modern masters Wolf Kahn, and Daniel Greene.
Pastels are made from the same pigments used to produce all colored art media, including oil paints. Instead of mixing oils, a binding agent is added to the pigments to create a chalk-like stick, which is applied to a textured surface, usually paper. Pastels are available in many colors, and paintings done centuries ago still maintain their original vibrancy today.
I am an immense fan of pastels because of their immediacy – no mixing colors or waiting for paint to dry. I use a variety of professional-grade soft pastels: Terry Ludwig, Unison, Richeson, Sennelier, and nuPastel. I use acid-free sanded paper/panel as my substrate: UArt pastel paper, PastelBord, and Sennelier pastel card.