What 1915 Georgia O'Keeffe drawings are famous for introducing pure abstraction to her work?

Georgia O'Keeffe's 1915 charcoal drawings are famous for introducing pure abstraction to her work.

After several years of teaching art, O'Keeffe began making a series of simplified charcoal drawings in 1915. These works used lines, curves, and shapes rather than recognizable objects, making them among the earliest purely abstract artworks produced by an American artist.

She sent some of the drawings to her friend Anita Pollitzer, who showed them to the photographer and gallery owner Alfred Stieglitz. Stieglitz exhibited them in 291, his New York gallery, in 1916. Their presentation helped launch O'Keeffe's public career.

The drawings are sometimes described as studies rather than finished paintings, but they were a decisive artistic breakthrough. They also helped establish O'Keeffe's reputation before she became known for flowers, New Mexico subjects, and large-scale abstract forms.