@ArneBab Hey, thank you! Yes, it can work in theory. I saw the other day a new generation of pencil: the 'mate' or 'black' (Staedler and Faber Castel) that behaves a bit like colored black pencils, and in general less shiny and metallic than usual pencils. If I see them on my artshop at next visit, I'll try them, because I'm curious also about trying to tone greyscale on my sketchbook as a softer alternative to what I do with ballpen right now but usual pencil shines a bit too much for me.