From pinterest.com/fifafufi27/юсуповы/юсупова-зинаида-ивановна-ур-нарышкина-1809-1893/; removed spots and flaws with Photoshop.
The split bodice and notched sleeves supplemented with cascades of lace make this portrait undatable.
Keywords: Robertson, Zinaida Yussupova the elder, Zinaida Naryshkina, Зинаиды Ивановны Юсуповой, Countess de Chauveau, Marchioness de Serres, Naryshkin family, Yussupov family, Russian, curly coiffure, hair jewelry, earrings, necklace, lace-edged chemise, modesty piece, off shoulder vee neckline, clasps, split bodice, quarter length notched close upper sleeves, lace cuffs