The whole concept of the image is beautiful to behold, but the real power is in the eyes that are stunning in their intense depth of studying something off camera, counterpointed by the highlighter light upon the dress and beads.
It doesn't quite fit the flavor of my "Favorites", but this is easily one of the most gorgeous photos I've ever seen. Everything here is working at an apex. The model is stunning, the lighting is perfect, the outfit and styling is excellent, and the photographer captured the moment perfectly.
Wonderful capture!
^^