Georgia O'Keeffe used charcoal as the primary medium in her early abstract drawings.
Her charcoal abstractions from 1915 and 1916 were among the first works that brought her national attention. These drawings used simplified lines, shapes, and flowing forms rather than recognizable subjects, and they helped establish her as an important early American abstract artist.
O'Keeffe later became especially famous for oil paintings of flowers, landscapes, and architectural forms, so charcoal is sometimes overlooked when people summarize her career. Her early drawings were not merely preparatory sketches; they were finished works with their own visual force.
Stieglitz exhibited several of these drawings at 291 in 1916. O'Keeffe eventually asked him to stop showing some of her early work because she felt exhibitions and interpretations were being controlled too much by others.