Stoneware clays are a favourite among potters for their versatility and durability. These clays, known for their nonporous nature, can be fired at high temperatures to achieve a range of finishes and strengths. Here’s a closer look at what makes stoneware clays a popular choice for ceramic artists.
Characteristics of Stoneware Clays
Stoneware clays are made from a mixture of clay minerals, including kaolin, ball clay, and fire clay. This blend creates a robust material that can withstand high firing temperatures, typically ranging from 1180 to 1280 degrees Celsius for glaze firings. The high firing temperature ensures that stoneware clays become vitreous, meaning they are nonporous and won’t absorb water, making them ideal for functional pottery like mugs, plates, and bowls.
Types of Stoneware Clays
There are several types of stoneware clays available, each with unique properties suitable for different pottery techniques and aesthetics:
- Traditional Stoneware: This type is known for its excellent workability and is suitable for both wheel throwing and hand-building. It typically has a smooth texture, making it easy to shape and mold.
- Fine Stoneware: Ideal for detailed work and fine pottery, fine stoneware clays have a smoother, more refined texture than traditional stoneware. They are excellent for creating intricate designs and delicate pieces.
- Coloured Stoneware: Available in a range of natural colours from grey to dark brown, coloured stoneware clays add a unique aesthetic to the final product. The colour variations are due to the different minerals present in the clay.
Firing and Glazing
One of the key aspects of working with stoneware clays is the firing process. Bisque firing, done at around 800 degrees Celsius, burns out organic impurities, creating a more durable surface for glazing. The subsequent glaze firing, ranging between 1180 and 1280 degrees Celsius, allows the glaze to mature, forming a glass-like surface that can be either glossy or matte.
When it comes to glazing, stoneware offers a wide variety of options, although some pigments and oxides may burn out at higher temperatures. It’s essential to test glazes on small tiles or cylinders to understand how they interact with different stoneware clays and firing conditions.
Applications of Stoneware Clays
Due to their strength and durability, stoneware clays are perfect for creating functional pottery and decorative pieces. They are widely used in making dinnerware, vases, and sculpture. Their ability to be both once-fired or twice-fired provides flexibility for potters to achieve the desired finish and durability.
Sajo Ceramics: Your Source for Stoneware Clays
Sajo Ceramics offers a wide range of stoneware clays suitable for all levels of pottery making. Our collection includes renowned brands such as Feeneys, Walker Ceramics, and Keane, ensuring that you have access to high-quality materials for your projects. Whether you are looking for traditional, fine, or coloured stoneware clays, we have the perfect options to meet your needs.
Explore our extensive selection of stoneware clays and find the ideal material for your next pottery project. With our expert advice and high-quality products, Sajo Ceramics is your go-to source for all your ceramics needs. Visit our stoneware clays collection today to learn more and place your order.