From Wikimedia.
This shows a young Countess Olga in a décollet´dress highlighted by a small brown vest.
Keywords: 1814, Molinari - Alexander, Olga Naryshkina, Olga Potokich Naryszkin, Olga Potocka, Potoka family, Naryszkin family, Countess, Russian, curly coiffure, bangs, ribbon headdress, square décolletage, over-bodice, cap over-sleeves, under-bodice, tight under-sleeves