Earthenware

From Encyclopedia Jr, free information reference for Kids

Earthenware is a common ceramic material, which is used extensively for pottery tableware and decorative objects. Although body formulations vary tremendously between countries, and even between individual makers, a generic composition is 25% ball clay, 28% kaolin, 32% quartz, and 15% feldspar. Earthenware is one of the oldest materials used in pottery. While red earthenware made from red clays is very familiar and recognizable, white and buff colored earthenware clays are also commercially available and commonly used.

Earthenware is typically bisque (or "biscuit") fired at a temperature of around 1000 to 1150 degrees Celsius (1800 to 2100 degrees Fahrenheit), and glaze fired (the final firing) at around 950 to 1050 °C (1750 to 1925 °F). The higher firing temperatures that fuse the body and glaze of other ceramics, will generally cause earthenwares to bloat. After firing the body is porous and opaque with colours ranging from white to red depending on the raw materials used.

Earthenware may sometimes be as thin as bone china and other porcelains, though it is not translucent and is more easily chipped. Earthenware is also less strong, less tough, and more porous than stoneware - but its low cost and easier working compensate for these deficiencies. Due to its higher porosity, earthenware must usually be glazed in order to be watertight.

[edit] Types of earthenware

• Creamware
• Delftware
• Faience
• Gouda (pottery)
• Majolica
• Raku
• Terra cotta

[edit] See also

• Pottery
• Porcelain

[edit] References

• An Introduction To The Technology Of Pottery. 2nd edition. P.Rado. Pergamon Press. 1988
• Whitewares: Production, Testing And Quality Control. W.Ryan & C.Radford. Pergamon Press. 1987
• Hamer, Frank and Janet. The Potter's Dictionary of Materials and Techniques. A & C Black Publishers, Limited, London, England, Third Edition 1991. ISBN 0-8122-3112-0.