This is the sort of tintype portrait I love most: stark looking subject, spare (and also quite painterly) sort of image. Here with just the edge of a lighthouse  (a painted backdrop I assume) making it into the frame. Some sort of apron (?) stretched across her lap, wedding ring exposed on those long fingers, cloth in the other hand. She looks a bit like a bird, and also makes me think of both Emily Dickinson and Georgia O'Keefe. 

 3 3/16" x 2 3/8". General light surface scratching and few more pronounced scratches near lower edge corner, all of a piece with it. No dings or bends.