And here it is. I combined clay with carrot pulp, left over from a juicing. I doubt that's been done before and look forward to when it has dried, so that I can test its properties.
Yesterday, I combined clay and the ducky-silt from below the duck pond, to make a slurry that I floated over the gap that had formed around the rim of the adobe on the fire-bath. It looks to have worked very well (guests tested the bath last night).
Tomorrow, I'm going to try a clay/sphagnum brick.