Grisure is a biobased ink that comes in several shades. From a light brown to a dark cold grey, these variations appear depending on the supply of ash. In the productions, we find a granular texture that is reminiscent of ash. The result is a rendering that enhances the value of the tool. In the context of this project, grisure is both a proposal for a material made from ash and a design tool. In fact, this ink has design constraints similar to those of certain other materials.