Authentic Chinese YiXin Zisha tea pot with cover, signed Chinese character seal mark at the bottom of the pot and 2 marks on the bottom of the lid It's not clay and it's not sandy mud. It's a special kind of rock which is mostly mineral deposits found under the ground near Yixing city. Nowadays the rock after it's mined are grounded by the machine with water, then it's filtered. The paste (just like the bean paste) is then used to make the teapots, Bonsai Pot, etc This paste is called Zisha Sand, because it contains very fine sandy particles. Height: 4 inches = 10 cm Length: 4-6 inches = 10-15 cm Approximate Weight: 300-400 g. Age: unknown. Provenance: from private collection in Florida, USA; purchased in 1980's -1990's Condition: Used, very good, no defects; Low Estimate: $500; High Estimate: $1,000; Original: Yes; Terms of sale: All sales are final! Buyer assumes all responsibility! No refunds will be given under any circumstances! No returns! Please, ask all you questions before you bid! If you have any doubts - do not bid!