From markfrm.blogspot.com/2014/10/11.html; the background was filled in with Photoshop to eliminate strong veiling reflections on the top and upper right side of the image.
Sophie has powdered her hair and put on a dress with vertical ribs on the short sleeves in this portrait.
Keywords: 1742, de Gasc, Sophie von Anhalt-Zerbst, Sophie of Anhalt-Zerbst, Catherine II, Catherine the Great, Princess, Tsaritsa, Ascania family, Romanov family, Russian, curly coiffure, hair jewelry, scoop neckline, lace modesty piece-bertha, elbow length close sleeves, lace forward-back flared engageantes, bows, vee waistline, full skirt, robes