porcelain results from the mixture of two main ingredients, Kaolin and
Petunse, fired at a temperature around 1300ºC. Kaolin is a refractory clay.
Because of heat resistance, it maintains its shape during the firing, and
is called the bone of porcelain by Chinese. In contrast, Petunse melts
at high temperatures and forms a nonprous natural glass, adding translucency
to porcelain. Chinese call it the flesh of porcelain. The desired result
determines the proportions of each ingredient.
Both Kaolin clay and Petunse rock were originally mined near JingDeZhen, "the capital of porcelain". To purify Kaolin, Chinese mix the clay with water to separate the pure and impure. Petunse rock was crushed to powder and then mixed with water to eliminate unwanted particles, then dried to smaller blocks called Petunse for distribution. Porcelain factories then crushed the Pedunse blocks into powder again, mixing them with water to make a soft paste for final use. The traditional method of porcelain making is still used in China today.
|Kaolin stone from Gaoling Village, JingDeZhen.
Before European discovered the ingredients of true porcelain, Chinese had used the Kaolin based clay for thousands of years.
|Clay hammer shed attached to porcelain factory, JingDeZhen|
|Clay hammer shed Settling tanks & drying, JingDeZhen|