While it is possible she is a living person, painted in 1784 as the artist's signature also notes, this painting has a feel of being a 19th century Grand Tour souvenir portrait 'aprés' or painted after an earlier painting. Still, frames in this fashion were used in France in late 1700s, but the size throws me off as it is larger than the typical late 1700s portraits. Sealed from the back side, I tool photos through the slightly convex old original cover glass, so allow for slight distortion. It is a strikingly beautiful painting, blue monochromatic palette, and nicely preserved. Still, a nice 3/4 pose, her clothing and hair certainly right for era, fichu scarf tied at bodice by a portrait miniature or possibly cameo on a long chain with slide. Measurements are noted on the photos.
Very good to excellent condition throughout. Pardon dust caught by digital photos and lighting. Rest assured, modern photography will capture every minuscule issue. I find no flaws to note. Charming 'freeze' of a moment typical to a woman of her era.