Aramis Antiques has dated this piece to the 1880s.
The whole is delicately painted but especially the face. The reverse bears a makers stamp - 15. The portrait is housed in a black lacquer frame, which has a minor chip at one corner, not surprising for an antique piece. The plaque itself is in excellent condition. The back has been relined with brown paper.
Image size 8cm high x 6.5cm wide.
Aramis Antiques has dated this piece to the 1880s.
You can view the stock and full dealer information on the Aramis Antiques Profile Page