This ewer (left) was made during the Liao dynasty, a period when the Khitan tribes-people took control of parts of northern China. Some kilns in the Hebei province that produced Xing ware came under this control, but were left to continue in their ceramic traditions, producing wares such as this ewer. It shares the Xing ware characteristics of a hard, white porcelain body and glaze. Xing ware was the earliest true porcelain made in China, and the world. The term porcelain is applied to ceramics made from a mixture a clay called kaolin and a white stone called Petuntse, which was fired at high temperatures. Porcelains differ from other ceramics in their impermeability, their whiteness and fine texture.