Signed by artist and dated c.1713, this is a depiction of Vicomte Charles de Beaufort. I am unable to find (quickly) a history for this French nobleman, though a generation or two earlier Le Duc François de Beaufort is perhaps his progenitor, and if so, the line goes back to King Henry IV of France, via his mistress Gabrielle d'Estrées. That story is full of intrigue and is one you'll wish to study, for the Duc is on of the characters in "Twenty Years After" and "The Vicomte de Bragelonne", both sequels to "The Three Musketeers" by Alexandre Duman. This miniature certainly has a look of the earlier de Beaufort (look for a portrait my Jean Nocret. I digress. This painting is quite superb - expressive eyes, costume, hair (wig, of course). A slight something disrupted the mouth a bit. Measurements noted on the photos.
Very good to excellent condition for age and type, some 300 years old. Artist signed and dated. No damage to painting but a something slightly disrupts the mouth. No chips nor cracks and no hairlines. It is gouache on thin wafer, backed by very old 'laid' paper, 100% cotton rag. Frame has rubs, consistent with advanced age. I have some doubt that it is as old as the signature, though the historic figure might well be. Typically, the very early 1700s portrait miniatures we've had are smaller, often housed in an etui, closing case of shagreen, leather, or maybe ivory. I think of this type of frame presentation more at end of 1700s. Just a note and experience to learn upon. It might be a later painting after an early one.