I remember when I first found this painting and thought it was a hand colored photograph, the detail and realism were of such quality. Taken from its frame and flat cover glass, one can see it is not a colored photo but an original work of art - painting on wafer, and it seems sad to me that the very talented artist did not sign his or her work. There is no information for us inside the frame, though you can see the artist added a reflective panel behind the face to brighten ti to view. Look at those eyes! Look at the hair and that Franz-Joseph beard or fashion. Clear blue eyes stare directly. Full measurements noted on the photos, but that face is a little larger than most miniatures, is 1 3/8" from chin to hairline.
Very good to excellent condition for age and type. I'd pin it at about c.1870-1900, more based on the fashion of the very well-dressed and elaborately bearded gentleman. A bit late for miniature portraits, since photography had almost stripped the profession and genre after the invention and proliferation of photography starting about c.1850s, from the c.1838 invention of the daguerreotype. One note: It seems to me someone has touched up a bit on his suit jacket toward lower 20%, where perhaps the original gouache or water color had deteriorated. View images to see what I mean. Not much discernible in frame. This one has a flat glass, which might indicate the old convex one, and a point in time for the slight loss/restoration. Otherwise, superb and excellent!