China clay or kaolin (Al₂Si₂O₅(OH)₄)
Kaolin, also known as China clay, is a high purity primary clay that is formed in the same place where it is found, which means that it has not been transported by wind or water. This gives it an essential characteristic: a low concentration of impurities, making it one of the purest materials in ceramics. Because of its purity, kaolin is essential in the production of porcelain, being the main ingredient that gives it its characteristics of whiteness and translucency when fired at high temperatures.
Kaolin is white in color and has a low plasticity, which makes it less suitable for hand or pottery wheel modeling techniques. However, its low plasticity does not detract from its importance, as it is indispensable in the manufacture of fine porcelain, due to its ability to withstand the high firing temperatures reached by porcelain kilns, without deforming or losing its properties. This thermal resistance is one of the reasons why kaolin is essential in high quality ceramics.
Fine porcelain, such as that of the Ming dynasty in China, one of the most valued ceramics in the world, is produced mainly from kaolin, known for its purity and resistance to extremely high temperatures.Interesting Fact
Kaolin is so pure that, in addition to its use in ceramics, it is also used in the production of paper, cosmetics and medicines.Helpful Tip
It mixes kaolin with feldspar or silica to improve its plasticity and workability, without losing the properties that allow it to vitrify.
