Comtesse de Choffault by Charles Berny d'Ouville in low-cut black velvet dress with white underslip, her parted black hair tied in ringlets, plait and plaited bun (auctioned by Christie's)
Medaille Signe Des Deux Faces (samovars.fr/objets-du-xixeme-et-avant/medaille-signe-des-deux-faces-r-b-baron) has this (approximately translated) about the work: This is actually the Countess of Chaffault, from an old family - Montbeliard, very established in Vendée during the Revolution. It is likely she is the second wife of the Earl of Chaffault Jacques Gabriel, Marie Renee Corice of Chaffault, born in 1790 at La Rochelle. She seems to be about 30/35 years, so the implementation date is about 1820-1825. The subject is shown from the front, in black dress with velvet neck and sheath of white, curly black hair separated with braid and braided wire, painted cloud and sky background. Signed 'Ch es. Berny' (bottom right).
From the berny-douville.blogspot; image lightened to bring out the waist belt by gogm.