Claudine Guérin de Tencin was a noted novelist and saloniste. Her Wikipedia article is here.
From tragoidiakomoidia.tumblr.com/post/356399964/female-hosts-of-the-french-salon; lightness added by gogm to bring out her coiffure.
This portrait of Mme. Claudine shows tight lacing dates back to ca. 1700. Her sleeve notches reveal elaborate lining and colorful under-sleeves. She wears a leather over-bodice seen in other French portraits of the day, such as the Duchesse du Maine. She appears to be wearing a wrap edged with a 10 cm wide white strip that in some way wraps around the sleeves.