She is also known as Maria Volkonskaya (next image). I cannot find out anything about this Maria Volkonskaya. Maria Raevskaya Volkonskaya is better known. There is also a Maria Mikhailovna Volkonskaya in the Belle Époque album.
Maria Kikin is dressed in the unmistakable Russian court style in this 1839 portrait by Sokolov. These dresses had spectacular embroidery done by specialist houses. The sleeves are part of the train, much like the hanging sleeves of a saya. The sleeves are quarter length before opening up in a long slit lined with white satin through which the arms emerge. For more about court dress is found here.
She carries her jeweled kokoshnik and her necklace and other jewels are setting on the nearby table top. She appears to be wearing black pearl earrings.
Keywords: 1839, Sokolov, Maria Kikina, Princess, Kikin family, Volkonsky family, Russian, side curl coiffure, kokoshnik, veil, lace, off shoulder straight neckline, Russian sleeves, lining, basque waistline, full skirt, train, jeweled bodice, jeweled skirt, necklace, earrings, bracelets, shoes, Lady-in-Waiting