Yixing teapots, called Zi Sha Hu in China and Purple Sand teapots in the U.S., are perhaps the most famous teapots. They are named for a tiny city located in Jiangsu Province, where a specific compound of iron ore results in the unique coloration of these teapots. They were fired without a glaze and were used to steep specific types of oolong teas. Because of the porous nature of the clay, the teapot would gradually be tempered by using it for brewing one kind of tea. This seasoning was part of the reason to use Yixing teapots. In addition, artisans created fanciful pots incorporating animal shapes.
Yixing teapots are meant for use with black and oolong teas, as well as aged puer tea. They can also be used for green or white tea, but the water must be allowed to cool to around 85 °C (185 °F) before pouring the water into the pot. Yixing teapots absorb a tiny amount of tea into the pot during brewing. After prolonged use, the pot will develop a coating that retains the flavour and colour of the tea. It is for this reason that soap should not be used to clean Yixing teapots. Instead, it should be rinsed with fresh water and allowed to air-dry. A studious tea connoisseur will only steep one type of tea in a particular pot, so as not to corrupt the flavour that has been absorbed.