I need practice shading basic forms, and I want to get more comfortable with charcoal. So I killed two birds with one stone. I made the setting with the Blender 3D program. As I was preparing the image for upload, I realized I got a little wonky with the near edge of the cube. The top of the cube is two large compared to the reference, and the shadow is a bit long. This is a three value study using vine charcoal, a kneaded eraser, and a fingertip, on 9x12 sketch paper with an underdrawing done with hard charcoal pencil.