A saggar is a ceramic, boxlike container used in the firing of pottery to enclose or protect ware in kilns. Traditionally saggars were made primarily from fireclay. Saggars have been used to protect, or safeguard, ware from open flame, smoke, gases and kiln debris: the name is a contraction of "safeguard". Their use is widespread, including in China, Korea, Japan and the United Kingdom. Saggars are still used in the production of ceramics to shield ware from the direct contact of flames and from damage by kiln debris. Modern saggars are made of alumina ceramic, cordierite ceramic, mullite ceramic and silicon carbide.
A Saggar Maker's Bottom Knocker was a job associated with the manufacturer of saggars in the UK, a name considered sufficiently amusing for it to be featured on the television panel show What's My Line?. Whilst sagger making was a skilled craft, bottom knocking was far less skilled, consisting of beating clay into a metal ring with a wooden mallet or Mawl. Young boys were often employed. The occupation is no longer needed as modern automated production techniques and far cleaner kilns, (not fired with coal or wood), do not require wares to be protected. Where an individual firing environment is required for other reasons, a one piece sagger is used.
Studio pottery use
From the 20th century studio potters have used saggars to create decorative ceramic pieces. In this use saggars are used to create a localised reducing atmosphere, or concentrate the effects of salts, metal oxides and other materials on the surface of their ware.
Some pots may be carefully prepared for saggar firing. One method creates a smooth surface covered with clay slip, terra sigillata, which responds particularly well to the saggar technique. This slip covering may be burnished to achieve a gloss. Prepared pots are nestled into saggars filled with beds of combustible materials, such as sawdust, less combustible organic materials, salts and metals. These materials ignite or fume during firing, leaving the pot buried in layers of fine ash. Ware produced in filled saggars may display dramatic markings, with colours ranging from distinctive black and white markings to flashes of golds, greens and red tones. Porcelain and stoneware are ideal for displaying the surface patterns obtained through saggar firing. In addition to the use of saggars, some studio potters bundle pots and burnable materials within a heavy wrapping of metal foil.
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