What type of works brought Georgia O'Keeffe to Alfred Stieglitz's attention in 1916?

Georgia O'Keeffe came to Alfred Stieglitz's attention through her charcoal abstractions.

In 1915, O'Keeffe created a pioneering group of nearly completely abstract charcoal drawings. She mailed some of these works to her friend and former teacher Anita Pollitzer, who showed them to the New York photographer and gallery owner Alfred Stieglitz. Stieglitz recognized their originality and exhibited them at his gallery, 291, in 1916.

This was a decisive turning point because it connected O'Keeffe with the New York avant-garde. Stieglitz's gallery had introduced American audiences to important European and American modernists, and he became a major advocate for O'Keeffe's work.

The charcoal drawings were not conventional landscapes or portraits. Their spare lines and abstract forms helped establish O'Keeffe as a distinctive modernist voice. Stieglitz later photographed her extensively, and the two married in 1924, but the charcoal series reached him first.