O’Keeffe enjoyed painting entire pictures in shades of black and white, the same restricted palette she used in dress. First in her absract drawings and watercolors in the 1910s, then in oil paintings of the 1920s, she made black and white into “colors” that were subtle and versatile. Sometimes she juxtaposed them; she also mixed the two and came up with a beautiful tonal range of grays. This narrow, vertical abstraction may have been informed by O’Keeffe’s paintings of modern skyscrapers of Manhattan in the late 1920s. (https://designlifenetwork.com/georgia-okeeffe-living-modern-virtual-tour/)