Phthalo blue (#000F89) and Sinopia (#CB410B) appear together across 1 master palette in our corpus, most prominently in the work of Nathan Altman and the Cubism tradition. Painters typically deployed phthalo blue at an average of 6% of the canvas, with sinopia at 29%. Third colors most often completing the combination include Platinum (#E5E4E2), Roman silver (#838996), and Violet-blue (#324AB2).