Saggar

A saggar is a type of kiln furniture. It is a ceramic boxlike container used in the firing of pottery to enclose or protect ware being fired inside a kiln. 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 the word 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 silicon carbide and in special cases from zirconia.

By far the largest number of UK pottery manufacturers were based in and around Stoke-on-Trent in a region known as The Potteries. Their businesses, locally known as potbanks, fired their wares in distinctive bottle ovens. At the turn of the twentieth century over 4,000 of these were in use, although by 2014 only 47 survive, all of which are no longer in production but are listed buildings.

The saggars were used for the biscuit and the glost firing. They were expected to last for about 40 firings; each potbank made their own in a saggar making workshop. Saggars were made from fireclay, by a saggar maker and two assistants: the framemaker and the bottom knocker. The framemaker beat the clay into a sheet on a metal table using a large mallet, the mow or mawl. Using a frame he would cut it to size, sprinkle it with sawdust and wrap it round a wooden block to make the walls. The framemaker was usually an apprentice in his late teens. The bottom knocker, usually a boy in his early teens, did the same on a smaller scale, constructing the round or banjo-shaped bottom. Again the mow was used to beat the air out of the clay and flatten the sheet. The saggar maker was an experienced craftsman who paid his assistants out of his piece-work earnings: he took the bottom and the sides onto a wheel and using his thumbs joined the sides to the bottom. The green saggars were dried and then placed on the top of bungs during the next firing of the kiln.

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