My earth oven. Made it from ideas in Kiko Denzers book. Not sure where you're located but Palmer Coking Coal's grey clay is the perfect mix. Just have to screen it and mix with water to make the mud and cob. I used wine bottles in the base to extend warmth. Back of the oven gets over 1200degrees F with 4 sticks of wood. One of the best things I've done in my back yard. Wish you good luck on yours.