Creative fire

It seems a bit brutal. Take piece of clay and make a sculpture. Fire it in the kiln and make it hard. Put on a glaze. Place it in a dustbin-like thing and direct a jet of gas inside until it reaches a temperature of 900 degrees. Let it cool down a little. Then take it out while it is still hot and place it in another bucket full of paper and wood chips - it will go on fire. Close the lid. The glaze will crack and be filled with carbon from the fire. Finally take the sculpture out. Carefully. Then clean it up.