Materials Matter: Soluble Carbon

Here is the product I've been using for my drawings lately. It's a "disc" (though it's mostly square) of solid carbon. It's easier to use than ink, for me, as I just dip the brush in water & then soak up some of the diluted carbon. Sort of like watercolor, which I don't use. I am in no way affiliated with this company (Art Graf), though if they want to make me an offer...
Also, it's made in Portugal, one of my favorite countries (though I haven't been there in many years).

The front of the packet

The details...now you know about as much as I do