Zisha

Zisha (宜興紫砂) is a type of Yixing clay from the region near the city of Yixing in Jiangsu Province, China, used in Chinese pottery since the Song dynasty (960–1279) .

Zisha is a mixture of kaolin, quartz and mica, with a high content of iron oxide. They are typically left unglazed.The best known Zisha wares made from Yixing clay are Yixing clay teapots, tea pets, and other teaware.

Yixing teawares are prized because their unglazed surfaces absorb traces of the beverage, creating a more complex flavour. The process of preparing the clay is lengthy and is traditionally regarded as a trade secret. Typical firing temperature is between 1100 – 1200 °C in an oxidizing atmosphere.

For these reasons, Yixing teawares should never be washed using detergents, but rather with water only. Connoisseurs recommend using each tea vessel for one kind of tea (white, green, oolong, black, or puer) or sometimes even one variety of tea only.