Fantastic. I think there are a few final touches that you could add. First, I recommend working on the shadow under the necklace on the left side of her neck. There doesn't seem to be any depth there and the necklace appears to be flat. I also recommend accentuating the dark areas (lowlights). The highlights look great, so the same must be done for the opposite.
Other than those small finishing touches, this is a great painting. Well done.