From day one we busted open 50 lb. sacks of clay, feldspar, and grog to make stoneware, earthenware, porcelain, and raku clay. Same as per glazes, engobes, lustres, slips, terra sig. In fact, the clay I’m using is mostly Kentucky Stone, about cone 8. Digging my own clay? It’s interesting but it rarely gets beyond bisque. On the other hand, I do make my own ash glazes, and I usually have a few pounds of new ash annually for this. It’s a by product of fireplace, firepit