I agree with ~mariabubu. Your technique works really well. I am glad we can learn from such an amazing drawings. ;] I adore the way you draw people - artistic and realistic at the same time, which is hard to do for most of people.
Really awesome! How did you get the translucid silkiness of the face and hair and the metallic shine on the focused areas? Is it just graphite pencil/ charcoal or did you use something else for accents?