I can find nothing about her other than she was mistress to Alexander I.
From pinterest.com/pin/305541155944038278/.
Marina's hat is topped with a turban. Her velvet dress has an ornamental laced bodice covering her chemise that has a high neckline.
Keywords: Marina Gurieva, Countess, Russian, curly coiffure, jeweled hat, puffed cloth ornaments, veil, chemise, high scoop neckline, long close sleeves, cuffs, laced bodice, square décolletage, strap sleeves, belt, jeweled buckle, natural high waistline, close skirt, earrings