The firing is done in a garbage can or in a pit. I use sawdust, wood, salt, oxides, plants, flowers & manure. I burnish my pots in 4 different stages to make a smooth soft surface. The pots smoke for 12 to 24 hrs. When finished the vessels are then polished with paste wax. There is no glaze on these pots. The colour is from the fire and additives. These vessels are not food or water safe.