Gustav Klimt painted this unfinished portrait in Vienna, though we don't know exactly when or with what. What strikes me is how much Klimt leaves open here. Look at how the white dress is made up of so many other colours. Lilac, grey, and small dabs of blue build up the form and create texture. You can almost feel the weave of the fabric. The thinness of the paint adds to this sense of light and air. If you look closely, you can see where he sketched the figure in with a dark under-drawing before applying the paint. It gives it a real sense of process, of how paintings are built up over time, layer by layer. There's an interesting relationship between this piece and Manet's work. Both artists share an interest in depicting modern life and a willingness to leave their process visible. With both, the beauty comes from seeing the painting being made, not just the finished product.