I thought for a change I'd get my charcoal pencils out. I haven't used charcoal for a while, I so love the feeling of the soft smooth application of charcoal with the rich tones so immediately achieved. I have 3 shades of pencil, dark, medium and light. I'm finding I can get the extremely fine detail of the eye by very lightly shading with the finely sharpened light pencil, then gently burnishing with a very fine colour shaper. The thing is with charcoal, you can't really erase any lines totally, maybe just lighten them a little so extreme care and concentration is required throughout. But I'm loving layering the deep dark tones. Another bonus is it is completely matt in finish so no light reflection that you get with graphite pencils.
This is about 18 inches square on my favorite Stonehenge paper. I'm using a reference photo from Savanna Images with kind permission of top wildlife photographer Billy Dodson.