There is a color version of this portrait on the Web - smaller and without provenance. Ekaterina Dashkova was a prominent figure in the Russian enlightenment, but the reactionary Paul I exiled her. According to Wikipedia, "Dashkova was the first woman in the world to head a national academy of sciences. Although not a scientist herself, Dashkova restored the failing institution to prominence and intellectual respectability. This came at a critical time in the history of science, its transformation from what was called natural philosophy, often practiced by gifted amateurs, to a professional enterprise." She corresponded with American Renaissance man Benjamin Franklin. Her Wikipedia article is here.