Portrait of Ambroise Vollard, 92x65cm, 1909-10, Pushkin Museum, Moscow. In the experience of practiced painting, Picasso entered mature rational analytical Cubist painting. At this time, his works emphasized the rational and rigorous reconstruction of forms; color became subordinate to the picture plane, with chiaroscuro variations in gray, black, and brown becoming the characteristic colors of this stage. These paintings were boldly almost abstract. The themes of painting at this stage were still lifes, especially those featuring guitars and violins, allowing the artist free rein. Works include The Mandolin Player and The Guitar Player (1911), the semi-relief sculpture Guitar (1912), and Violin (1915).