Vintage Ceremonial Yixing Zisha Teapot with Calligraphy. Also known as Zisha Ware, which is a traditional type of Chinese stoneware. It's made from a special clay found near the city of Yixing in Jiangsu Province, China. These teapots are highly valued for their ability to enhance the flavour of tea. The clay, called Zisha, is rich in iron and other minerals. The clay is known for it's porous nature allowing the teapot to absorb trace amounts of tea flavours and minerals over time. They are traditionally handmade and can have intricate designs and calligraphy. They are typically unglazed. Zisha can be broadly categorized into three colours: purple, red and beige. The deeper the colour the higher the concentration of iron in the clay. Purple Zisha is purple sand/clay. This stoneware has a purple-red-brown colour. The bottom of the teapot is stamp marked, as is the inside of the lid, but you can only just make out the lid stamp. The spout end inside the pot has small poked through strain