For aspiring potters, one of the first and most crucial steps is sourcing the right clay. Clay is the very foundation of pottery, and the type you choose can significantly impact your creative process and the final product. Understanding the different types of clay and where to find them is essential for any potter, whether you’re just starting or looking to expand your practice. Several slightly different types of clay are used for different types of pottery, but clay can be classified into 6 main types that are used commonly among potters.
The predominant types of pottery clay are earthenware, stoneware and porcelain, but a mix of other clays to make them easier to handle may be preferable.Earthenware Clay
Earthenware clay is often the first choice for beginner potters because it’s generally easier to work with and more forgiving. Known for its rich, warm colors, earthenware has high plasticity, making it easy to manipulate. It’s primarily composed of iron and mineral impurities, giving it unique properties. Earthenware matures at a lower firing temperature, generally between 950°C and 1,100°C (1,745°F and 2,012°F), which is ideal for beginners. However, it’s more fragile and less versatile than other types of pottery once fired. It can be used to make items that hold food stuff and liquid in the forms of bowls or plates.
Stoneware Clay
Stoneware clay is a durable and versatile option known for its ability to withstand high firing temperatures, typically between 1000°C and 1380°C. Stoneware clays contain mineral impurities such as silica, feldspar, ball clay, and quartz. It becomes stone-like and durable when fired, making it suitable for practical applications like dinner plates and vases. Stoneware doesn’t have the same porosity as earthenware and is perfectly suited for holding liquids and foodstuffs.
Porcelain Clay
Porcelain clay is highly sought after for its durability, delicate appearance, and elegant finish, though it can be more challenging to work with. It’s sometimes known as kaolin, and is almost purely made up of kaolin clay, with occassional amounts of quartz and feldspar when manufactured. There are three types of porcelain ceramics: hard-paste, soft-paste, and bone china. Porcelain can be difficult to work with, requiring a lot of water due to its large number of clay particles. Firing porcelain gives it a glass-like appearance, and it is often fired more than once to achieve different finishes.
Sourcing Clay: Local and Online Options
When it comes to buying clay, you have several options, each with its own advantages and disadvantages. Local pottery supply stores are a fantastic resource. These stores offer a wide selection of clay types, and perhaps more importantly, expert advice. You can physically inspect the clay, assess its texture and workability, and get recommendations tailored to your specific projects and skill level.
Ceramic centers and art schools are another excellent local resource. Many centers and schools sell clay to students and members, often at a discounted rate. They can also provide valuable insights into the best clay for your needs and offer workshops and classes to improve your pottery skills. However, the selection may be limited compared to specialized supply stores, and access might be restricted to students or members.
Online retailers offer a convenient and expansive selection of clay. Websites often have detailed product descriptions and customer reviews, which can help you make informed decisions. However, buying clay online has its drawbacks. The cost of shipping can be significant, especially for heavy clay, and you can’t physically inspect the clay before purchasing. It’s essential to carefully consider these factors before making an online purchase.
Digging and Processing Your Own Clay
For the adventurous potter, digging and processing your own clay can be a rewarding experience. It allows you to connect with the earth and create pottery from materials you’ve personally sourced. This process involves several steps, including locating a suitable clay deposit, digging the clay, removing impurities, and testing its properties.
However, digging your own clay presents several challenges. It can be physically demanding and time-consuming, and identifying a usable clay deposit requires knowledge and experience. You’ll also need to test the clay’s firing temperature and shrinkage rate to ensure it’s suitable for your projects. Ethically, it’s important to consider the environmental impact of digging clay. Obtain permission from landowners and avoid disrupting natural habitats. Sustainable harvesting practices ensure that clay resources are available for future generations. For a sustainable approach to pottery, explore eco-friendly clay practices.
Assessing Clay Quality and Storage
Before purchasing clay, it’s crucial to assess its quality to ensure it meets your needs and skill level. Look for clay that is smooth and free of lumps or debris. The clay should be pliable and easy to work with, without being too sticky or crumbly. Consider the clay’s firing temperature and shrinkage rate, as these factors will affect the final outcome of your pottery.
Proper storage is essential to maintain the workability of your clay. Clay should be stored in an airtight container or wrapped tightly in plastic to prevent it from drying out. If the clay becomes too dry, you can add water to rehydrate it, but be careful not to add too much, as this can make the clay too soft. Regularly check your stored clay and re-wedge it to maintain its consistency. To ensure your clay remains in top condition, learn more about mastering clay storage and aging.
