I have collected roadside clay and fired it in the woodstove at our cabin with great success, and lots of fun doing it. Firepit on the beach not so successful, due to wind. I also brought some clay home, sieved the bigger rocks out, and threw it on my wheel. These came out a nice toasty orange-red at 04, darker brown when glazed clear and fired 05. Totally vitrified but not distorted at ^6. I'm going to try some of the clay in some ^6 line blends for glazing. The greatest success for woodstove firing was some rather thick 5 inch tiles with relief animal designs on them. Lots of fun.