Purple Clay, also known as 'Zisha', is a rare natural mineral resource comprised of clay and other minerals such as quartz buried deep underground for years. Although it named "purple clay" it is usually rosely-brown in color. There will be some other colors appear as well, due to its unique blend of minerals. We seldom add artificial color to paint purple clay product as the sophisticated natural color is highly appreciated. Experienced artist could magically turn the purple clay to a refined product.