Unlike normal clay, which is soft, with a moist consistency, zi sha is more like a hard rock and after various manipulations it becomes suitable for the production of dummies. That’s why it cannot be used on the potter’s wheel – only manual or final production (assembly and gluing of parts together) and casting.
The clay is layered: the upper ones are soft, from which they produce everyday and cheap dishes, including teapots. The deeper, the more petrified the clay and the higher the quality of the dishes that derive from it and, consequently, the price.
There are different proportions to mix these clays together, different additives (metal oxides, sand, calcined fragments, mica and pyrite), the technology uses different cooking temperatures and the atmosphere in the furnace – all this creates a wide range of colors (from yellow to black) and textures, making the finished teapots so different. They can have a smooth and granular surface, up to simulating the peel of citrus fruits, with tubercles and dents: it all depends on the owner and his idea
Why Zi Sha Yixing clay is good?
Yixing clay has a lot of kaolin, which allows you to burn teapots at very high temperatures, as well as iron, silicon and small silicate particles, which gives the finished teapots shine and porosity, thanks to which the teapots pass oxygen inside and allow the tea to breathe.
Due to the high firing temperature, teapots with all their apparent fragility are very durable. The porous structure allows the teapot to heat up quickly and keep warm for a long time, avoids temperature differences during tea drinking, which affect the taste very badly. The handle of the kettle never heats up.
Due to the porous structure, essential oils are absorbed by the walls of the teapot, and over time, such a teapot improves the taste of tea, makes it softer, deeper, adding its own unique taste from accumulated essential oils.