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Earthenware pottery

Earthenware is a common ceramic material, which is used extensively for pottery tableware and decorative objects. The word ceramic is derived from the Greek word κεραμικός ( keramikos) Pottery is the Ceramic ware made by potters It also refers to a group of materials that includes Earthenware, Stoneware 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. Clay is a naturally occurring material composed primarily of fine-grained Minerals which show plasticity through a variable range of Water content, and Kaolinite is a Clay mineral with the chemical composition Al 2 Si 2 O 5( OH)4 Quartz (from German) is the most abundant Mineral in the Earth 's Continental crust (although Feldspar is more common in Feldspar is the name of a group of rock-forming Minerals which make up as much as 60% of the Earth 's crust. Earthenware is one of the oldest materials used in pottery. Pottery is the Ceramic ware made by potters It also refers to a group of materials that includes Earthenware, Stoneware 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 commonly bisque, or biscuit, fired to temperatures in the range of 1000 and 1150 degrees Celsius (1800 and 2100 degrees Fahrenheit, and glost fired from 950 to 1050°C (1750 to 1925°F). The Celsius Temperature scale was previously known as the centigrade scale. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 However examples of the the reverse, low biscuit firing and high glost, can also be found: this can be popular with some studio potters where bisque temperatures may be 900 to 1050°C (1650 to 1920°F ) with glost temperatures in the range of 1040 to 1150°C (1900 to 2100°F). The exact temperature will be influenced by the raw materials used and the desired characteristics of the finished ware. The higher firing temperatures are likely to cause earthenware 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. Bone china is a type of Porcelain body first developed in Britain in which calcined Cattle bone ( Bone ash) is a major constituent Porcelain is a Ceramic material made by heating raw materials generally including Clay in the form of Kaolin, in a Kiln to temperatures Earthenware is also less strong, less tough, and more porous than stoneware - but its low cost and easier working compensate for these deficiencies. Porosity is a measure of the void spaces in a material and is measured as a fraction between 0–1 or as a Percentage between 0–100% Stoneware a Vitreous or semivitreous ceramic ware of fine texture made primarily from nonrefactory fire clay Due to its higher porosity, earthenware must usually be glazed in order to be watertight. Porosity is a measure of the void spaces in a material and is measured as a fraction between 0–1 or as a Percentage between 0–100% Glaze is a layer or coating of a Vitreous substance which has been fired to fuse to a ceramic object to color decorate strengthen or waterproof it

Contents

Types of earthenware

Painted, incised, and glazed earthenware. Dated 10th century, Iran. New York Metropolitan Museum of Art.
Painted, incised, and glazed earthenware. Dated 10th century, Iran. For a topic outline on this subject see List of basic Iran topics. New York Metropolitan Museum of Art.

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Dictionary

earthenware

-noun

  1. An opaque, semi-porous ceramic made from clay and other compounds.
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