Her face is only 1/2", chin to hairline, and her portrait would have been done in late 1700s based on her fashion. The gauzy shawl is called a 'fichu', and her hair is powdered and worn in the style of her time c.1770-90s. I do not think the information on backside has anything to do with her, but is simply a printed page the framer or artist has used as a backing. Original convex cover glass has been cleaned and she shows beautifully, no flaws to note. Full measurements noted on the photos.
Excellent condition for age and type, long and well preserved, there are no flaws to reveal or point out. A fine one from my collection, both for its age and costume, and for the tiny painting of her face.