Georgia O'Keeffe used charcoal for the abstract drawings Alfred Stieglitz exhibited in 1916.
In 1915, while teaching in South Carolina, O'Keeffe began making a series of nonrepresentational drawings with charcoal on paper. These works reduced form to lines, curves, and tonal relationships rather than depicting recognizable objects. She sent some of the drawings to her friend Anita Pollitzer, who showed them to Alfred Stieglitz without O'Keeffe’s initial permission.
Stieglitz exhibited the drawings at his 291 gallery in 1916. The display was important because it introduced O'Keeffe to the New York modernist circle and helped establish her reputation before she became known for large flower paintings. O'Keeffe later worked in oil, watercolor, pastel, and other media, so charcoal is specifically tied to this breakthrough group. The drawings are sometimes described simply as abstractions, but the medium matters: they were charcoal-on-paper works, not oil paintings.