Firing pottery without a kiln is possible but requires outdoor space and plenty of wood. Modern artisans can accomplish this time-consuming task by borrowing a technique used by ancient Native American tribes. Clay must be heated to a temperature of 1,000 degrees F to become hardened pottery. Tribes used open flames to heat clay to 1,400 degrees F to make earthenware for the creation of tools, storage and cooking items. Clay will break if heated to temperatures in excess of 2,400 degrees F.
Things You'll Need
Safe space for an outdoor fire ring
Fire safety equipment such as extinguisher, goggles, gloves, tongs
High temperature thermometer (available at pottery supply and hardware stores)
Create a fire ring in an open setting. Follow all local burning laws. Use fire safety equipment and have extinguishers on hand.
Place bricks inside the fire ring to hold the clay items.
Put clay on the bricks using fire-safe tongs.
Cover pottery stack with a layer of animal manure. The animal waste insulates the heat around the clay.
Add a layer of clay, straw or sand to the top of the manure layer.
Poke a 3-inch opening in the top of the mound layer to vent the heat.
Poke additional same-size holes around the bottom mound layer for airflow.
Ignite the fire through the bottom vent holes.
Follow clay package instructions for heating times. Insert the high temperature thermometer through any bottom hole to gauge heat. Heat clay to 1,400 degrees F. Poke additional air holes to lower heat temperatures if the fire reaches in excess of 2,200 degrees F. Clay cracks at a temperature of 2,400 degrees F. Size or number of clay items does not change temperature guidelines.
Extinguish fire. Remove and clean pottery thoroughly.
Check with local law enforcement or the fire department regarding burning laws and fire safety procedures before starting this project. Native American black pottery can be created over an open fire. To create black pottery, do not poke any vent holes in the mounds.