The ashes of wood fired in a hearth or furnace, of inconsistent quality. This type of ash is used to make glazes for ceramics after it has been thoroughly drained and watered. It is often used for coarse wares and not for high quality wares.
Some Korean ceramics are often glazed with a milky glaze because they are made from the ashes, which have a high silicic acid content due to the burning of rice plants as fuel for the furnace.
