Yixing Clays and Old Teapots
the best clay you can get in modern times
GU Jingzhou 顾景舟双线竹鼓壶
Black Dotted Clay Artificially Made with manganese 黑星土
On the internet when they say they are Black Dotted Clay , they really means they are Black Dotted Clay Artificially Made with manganese .
Republic Green 民国绿
This clay was created by adding Cobalt Minerals, not Chemicals as commonly used today