The first pic is a quick 10 minute block-in using pan pastels and a small palette knife/trowel with soft tip as an applicator.
The next pic shows about 30 minutes work with an eraser, trying to find the forms.
Next is the first application with charcoal pencil. I rubbed down with a paper towel. About 30 more minutes.
Here's where I'm at now. This is after white was used, and again rubbed down to get the values closer together. This was about 45 minutes.
The process is about refining with each step. I see things now that need fixing. So each time I go back in, re-draw, brush or rub down, it gets more correct. At least that is the hope.Worked on it about another hour tonight. I'm including the finish and a detail shot.