I use soft pastels to make my own washes - I carefully scrape the pastel stick with a scalpel blade, to get a fine powder, then add a few drops of washing up liquid ( to reduce the surface tension ), then carefully add water, to get the desired consistency. It takes a bit of trial & error, but you cam mix any colour you like. As Tim says, they aren't very robust, you need a varnish coat over them to seal them in.
Dave
Dave
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