Kaolin in the context of "Cozzi porcelain"

Soft-paste porcelain (sometimes simply "soft paste", or "artificial porcelain") is a type of ceramic material in pottery, usually accepted as a type of porcelain. It is weaker than "true" hard-paste porcelain, and does not require either its high firing temperatures or special mineral ingredients. There are many types, using a range of materials. The material originated in the attempts by many European potters to replicate hard-paste Chinese export porcelain, especially in the 18th century, and the best versions match hard-paste in whiteness and translucency, but not in strength. But the look and feel of the material can be highly attractive, and it can take painted decoration very well.

The ingredients varied considerably, but always included clay, often ball clay, and often ground glass, bone ash, soapstone (steatite), flint, and quartz. They rarely included the key ingredients necessary for hard-paste, china clay including kaolin, or the English china stone, although some manufacturers included one or other of these, but failed to get their kilns up to a hard-paste firing temperature. They were called "soft paste" (after the French "pâte tendre") either because the material is softer in the kiln, and prone to "slump", or their firing temperatures are lower compared with hard-paste porcelain, or, more likely, because the finished products actually are far softer than hard-paste, and early versions were much easier to scratch or break, as well as being prone to shatter when hot liquid was suddenly poured into them.

Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al₂Si₂O₅(OH)₄), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces.

Clay minerals form in the presence of water and have been important to life, and many theories of abiogenesis involve them. They are important constituents of soils, and have been useful to humans since ancient times in agriculture and manufacturing.

Hard-paste porcelain, sometimes called "true porcelain", is a ceramic material that was originally made from a compound of the feldspathic rock petuntse and kaolin fired at a very high temperature, usually around 1400 °C. It was first made in China around the 7th or 8th century and has remained the most common type of Chinese porcelain.

From the Middle Ages onwards, it was very widely exported and admired by other cultures and fetched huge prices on foreign markets. Eventually Korean porcelain developed in the 14th century and Japanese porcelain in the 17th, but other cultures were unable to learn or reproduce the secret of its formula in terms of materials and firing temperature until it was worked out in Europe in the early 18th century and suitable mineral deposits of kaolin, feldspar, and quartz were discovered. This soon led to a large production in factories across Europe by the end of the 18th century.

Ding ware, Ting ware (Chinese: 定瓷; pinyin: Dìngcí) or Dingyao are Chinese ceramics, mostly porcelain, that were produced in the prefecture of Dingzhou (formerly romanized as "Ting-chou") in Hebei in northern China. The main kilns were at Jiancicun or Jianci in Quyang County. They were produced between the Tang and Yuan dynasties of imperial China, though their finest period was in the 11th century, under the Northern Song. The kilns "were in almost constant operation from the early eighth until the mid-fourteenth century."

The most characteristic wares are thin porcelains with a white or greyish body and a nearly transparent white-tinted glaze, though they are classed as stoneware by some. Chemical analysis has shown that they were often made entirely of a kaolinitic clay without any petuntse or "porcelain stone". They are mostly decorated with uncoloured designs that are incised or in very shallow relief.

Diaspore (/ˈdaɪ.əˌspɔːr/) – also called diasporite, empholite, kayserite, or tanatarite – is an aluminium hydroxide oxide mineral, α-AlO(OH), crystallizing in the orthorhombic system and isomorphous with goethite. It occurs sometimes as flattened crystals, but usually as lamellar or scaly masses, the flattened surface being a direction of perfect cleavage on which the lustre is markedly pearly in character. It is colorless or greyish-white, yellowish, sometimes violet in color, and varies from translucent to transparent. It may be readily distinguished from other colorless transparent minerals with a perfect cleavage and pearly luster (e.g. mica, talc, brucite, and gypsum) by its greater hardness of 6.5–7. Its specific gravity is 3.4. When heated before the blowpipe, it decrepitates violently, breaking up into white pearly scales.

The mineral occurs as an alteration product of corundum or emery and is found in granular limestone and other crystalline rocks. Well-developed crystals are found in the emery deposits of the Ural Mountains and at Chester, Massachusetts, and in kaolin at Schemnitz in Hungary. If obtainable in large quantity, it would be of economic importance as a source of aluminium.

Conté (/ˈkɒnteɪ, -ti/; French: [kɔ̃te]), also called the Conté stick or Conté crayon, is a drawing medium composed of compressed powdered graphite or charcoal mixed with a clay base, square in cross-section. It was invented in 1795 by Nicolas-Jacques Conté, who created the combination of clay and graphite in response to the shortage of graphite caused by the Napoleonic Wars (when the British naval blockade of France prevented import). Conté crayons had the advantage of being cost-effective to produce, and easy to manufacture in controlled grades of hardness.

They are now manufactured using natural pigments (iron oxides, carbon black, titanium dioxide), clay (kaolin), and a binder (cellulose ether).

The use of medicinal clay in folk medicine goes back to prehistoric times. Indigenous peoples around the world still use clay widely. Such uses include external application to the skin and geophagy. The first recorded use of medicinal clay goes back to ancient Mesopotamia.

A wide variety of clays are used for medicinal purposes—primarily for external applications, such as the clay baths in health spas (mud therapy). Among the clays most commonly used are kaolin and the smectite clays such as bentonite, montmorillonite, and Fuller's earth. However, their use is declining, and modern evidence-based medicine has ended the use of many types.