Skeleton sketch charcoal

I have just done a charcoal sketch of another Skelton models. I feel the sketch has come out very good. It was only a 15 min task so it is not finished. But so far I feel it has come out well. As from my previous posts I am quite a messy free hand sketch drawer, so charcoal plays to my strengths as unlike pencil or paint you get a much freer and expressive feel to your pieces. This sketch isn't one of my best as some of the sizing on the skeleton was off. However there are still elements within it that i like and that is worth analysing.

Personally i feel the hips are the best element to my sketch- the features even though they are rough and sketch like are very defined and add a good depth and lots of contrast between the light and dark.