I've used water-soluble graphite pencils with and without wood (the latter not needing sharpening) but water-soluble sticks of graphite in three different hardnesses, similar in shape and size to hard Conté sticks, I hadn't tried before so some just had to come home with me. (It's never hard to find a reason is it!)
Yesterday I tried them for the first time, during the last drawing of the first day of an art workshop I'm doing at Higham Hall in the English Lake District, along with some softer, water-soluble art sticks and 'ordinary' pencil. I like the dark line the softest graphite stick produced, but in places had trouble getting the stick to work and suspect it might've been slipping on the color. Next I want to try it just by itself, with a brush, water, and an eraser. Certainly it's a medium that bridges the distinction between painting and drawing!
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