Wood fired ceramics have been fired in a kiln fuelled by the burning of timber. The ash from the flow of flame through the kiln is deposited on the surfaces of the pots. At high temperature this ash melts and fuses with the clay to form a natural and usually uneven glaze. It is possible to read a wood fired pot by following the path of the flame across its surface.
The process last the course of many hours of labour intensive stoking. This requires high concentration from the potter who is rewarded by a deep understanding of the nature of fire and its action upon their work. Exhausting but deeply satisfying.