Q:

What are the different types of clay?

A:

There are over thirty types of clay, but in pottery these types are divided into the three main classes of earthenware clay bodies, mid-fire stoneware clay bodies and high-fire stoneware clay bodies. These three classes are sometimes described as earthenware, stoneware and porcelain, respectively, after the type of pottery these clays make.Clays fired at higher temperatures tend to be less permeable.

These categories of clay are based on how long and at what temperature the clay must be fired in order to reach maturation, or its optimal hardness. Each category includes clays with different colors and degrees of workability. Clay colors are caused by impurities. For instance, red clay generally contains a high level of iron relative to other clays, and black clay contains manganese. Clay workability refers to how plastic the clay is. Higher levels of kaolin make clays less plastic, but also less porous.

Porcelain clays have the highest firing temperature. They are made of fine-grained white clays with high levels of kaolin. Stoneware clays fire at a medium temperature and are exceptionally durable and non-porous. Stoneware clays are often buff, brown or gray due to low levels of impurities. Earthenware clays have the lowest firing temperatures, but they are often more porous and less durable. Because of the low firing temperature achievable in a simple pit fire, earthenware was the first form of fired ceramic invented by humans. Earthenware is often called terra cotta or simply pottery.


Is this answer helpful?

Similar Questions

  • Q:

    What are some of the different types of soil?

    A:

    There are three basic types of soil, which are categorized by their mineral particle sizes, and they are clay, silt and sand. Clay soil contains very fine mineral particles. Silt is also fine but to a lesser degree than clay, while sand contains large, coarse particles.

    Full Answer >
    Filed Under:
  • Q:

    Where is clay found?

    A:

    Clay is one of the most common minerals and is mainly found on or near the surface of the Earth. Nearly all civilizations have used it to make pots, bricks and tablets.

    Full Answer >
    Filed Under:
  • Q:

    What are the four basic types of soil?

    A:

    The four basic types of soil are sand, silt, clay and loam. Loam, considered a perfect soil, is a mixture of silt, clay and sand. Sand is gritty and contains small particles of minerals and rocks, where silt is smoother than sand and is more fertile.

    Full Answer >
    Filed Under:
  • Q:

    What are coniferous forest soil types?

    A:

    The most common types of soils in coniferous forests are called podzol soils. Podzol soils are defined by their thin surface layers and high acid content. Their composition varies depending on their location on earth and is subject to variation from temperature differences and geographical factors, such as terrain and the presence or absence of air, water and minerals.

    Full Answer >
    Filed Under:

Explore