Pottery is the ceramic ware made by potters. It also refers to a group of materials that includes earthenware, stoneware, and porcelain. The places where such wares are made are called potteries.
Additives can be worked into the clay body prior to forming, to produce desired effects in the fired wares. Coarse additives, such as sand and grog a fired clay which has been finely ground are sometimes used to give the final product a required texture. Contrasting colored clays and grogs are sometimes used to produce patterns in the finished wares. Colorants, usually metal oxides and carbonates, are added singly or in combination to achieve a desired color. Combustible particles can be mixed with the body or pressed into the surface to produce texture.
Agateware: So-named after its resemblance to the quartz mineral agate which has bands or layers of color that are blended together. Agatewares are made by blending clays of differing colors together, but not mixing them to the extent that they lose their individual identities. The wares have a distinctive veined or mottled appearance. The term 'agateware' is used to describe such wares in the United Kingdom; in Japan the term neriage is used and in China, where such things have been made since at least the Tang Dynasty, they are called marbled wares. Great care is required in the selection of clays to be used for making agatewares as the clays used must have matching thermal movement characteristics.
Glaze is a glassy coating applied to pottery, the primary purposes of which include decoration and protection. Glazes are highly variable in composition but usually comprise a mixture of ingredients that generally, but not always, mature at kiln temperatures lower than that of the pottery that it coats. One important use of glaze is in rendering pottery vessels impermeable to water and other liquids. Glaze may be applied by dusting it over the clay, spraying, dipping, trailing or brushing on a thin slurry composed of glaze minerals and water. Brushing tends not to give an even covering but can be effective as a decorative technique. The color of a glaze before it has been fired may be significantly different than afterwards. To prevent glazed wares sticking to kiln furniture during firing, either a small part of the object being fired is left unglazed or, alternatively, special refractory spurs are used as supports.
These are removed and discarded after the firing. Special methods of glazing are sometimes carried out in the kiln. One example is salt-glazing, where common salt is introduced to the kiln to produce a glaze of mottled, orange peel texture. Materials other than salt are also used to glaze wares in the kiln, including sulfur. In wood-fired kilns fly-ash from the fuel can produce ash-glazing on the surface of wares.
Additives can be worked into the clay body prior to forming, to produce desired effects in the fired wares. Coarse additives, such as sand and grog a fired clay which has been finely ground are sometimes used to give the final product a required texture. Contrasting colored clays and grogs are sometimes used to produce patterns in the finished wares. Colorants, usually metal oxides and carbonates, are added singly or in combination to achieve a desired color. Combustible particles can be mixed with the body or pressed into the surface to produce texture.
Agateware: So-named after its resemblance to the quartz mineral agate which has bands or layers of color that are blended together. Agatewares are made by blending clays of differing colors together, but not mixing them to the extent that they lose their individual identities. The wares have a distinctive veined or mottled appearance. The term 'agateware' is used to describe such wares in the United Kingdom; in Japan the term neriage is used and in China, where such things have been made since at least the Tang Dynasty, they are called marbled wares. Great care is required in the selection of clays to be used for making agatewares as the clays used must have matching thermal movement characteristics.
Glaze is a glassy coating applied to pottery, the primary purposes of which include decoration and protection. Glazes are highly variable in composition but usually comprise a mixture of ingredients that generally, but not always, mature at kiln temperatures lower than that of the pottery that it coats. One important use of glaze is in rendering pottery vessels impermeable to water and other liquids. Glaze may be applied by dusting it over the clay, spraying, dipping, trailing or brushing on a thin slurry composed of glaze minerals and water. Brushing tends not to give an even covering but can be effective as a decorative technique. The color of a glaze before it has been fired may be significantly different than afterwards. To prevent glazed wares sticking to kiln furniture during firing, either a small part of the object being fired is left unglazed or, alternatively, special refractory spurs are used as supports.
These are removed and discarded after the firing. Special methods of glazing are sometimes carried out in the kiln. One example is salt-glazing, where common salt is introduced to the kiln to produce a glaze of mottled, orange peel texture. Materials other than salt are also used to glaze wares in the kiln, including sulfur. In wood-fired kilns fly-ash from the fuel can produce ash-glazing on the surface of wares.
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