YiXing teapots are small enough to be considered personal brewing devices, holding one or two tea servings at most. The YiXing region is located 120 miles northwest of Shanghai, and it is known for a special kind of clay called zisha: zi means purple and sha means sand, although despite of the etymology of the word, zisha clay can be found in colors other than purple, such as red, yellow, green and blue. YiXing teapots have an endless variety of shapes and colors, but their main feature is purely functional: these teapots are not glazed and have the ability to absorb the tea flavor with continued usage. The fired clay contains tiny air pockets for insulation, which means that if one brews the same type of tea all the time, each brewing is a bit more flavorful than the one before, since the interior air pockets of the teapot absorb and retain the flavor of the brew. Although organized cultivation of Camellia Sinensis, the common tea plant, dates back to the IV century, the manufacturing of YiXing personalized tea-brewing pots did not begin until the Sung Dynasty (X to XII centuries), and did not become widely accepted until the Ming Dynasty (XIV to XVII centuries). The dissemination of YiXing ware, after it was initially brought to the Europe by the East India Trading Company, not only influenced the forms of European teapots, but also prompted the invention of hard-paste porcelain in the Western world.
