Also known as "kiln color".

Under-glaze color is a main decorative means of ceramics, which is to draw various decorative patterns on the green body (semi-finished product) that has been molded and dried by pigment, then cover it with white transparent glaze or other light-colored surface glaze, and then put it in a kiln for one-time firing at high temperature (1200- 1400℃).

The pattern after firing is covered by a transparent glaze film, and the surface is bright, soft, smooth and not protruding, which is crystal clear.

Its characteristics are well-preserved color and long duration.

We usually see blue-and-white porcelain, underglaze red porcelain, blue-and-white underglaze red porcelain, underglaze tricolor porcelain, underglaze colored porcelain and so on, all of which are fine classifications of underglaze colored porcelain.

Under-glaze color is a kind of color that is directly coated on porcelain blank with pigment, covered with a layer of transparent glaze, and sintered with porcelain once in a high temperature atmosphere after entering the kiln.

Its outstanding advantages are no wear, no fading, no lead and no toxicity, smooth and flat, and simple operation.

Jingdezhen blue-and-white porcelain is the most successful underglaze porcelain in Yuan, Ming and Qing Dynasties, and it is also one of the representative varieties of China porcelain.

Underglaze colors include blue and white, underglaze red, underglaze color, underglaze color, underglaze color, underglaze color and underglaze color.

The appearance of underglaze colored porcelain can be traced back to the Three Kingdoms period at the end of Han Dynasty, but the porcelain at that time was simply decorated with Hershey pigments, without deliberately drawing decorative patterns.

The real underglaze porcelain should appear in the Tang Dynasty.

At that time, craftsmen in Changsha Kiln, Hunan Province used iron oxide and copper oxide as pigments, painted different patterns on the blank, or wrote words and poems, then applied green glaze, and fired them at 1220℃~ 1270℃.

Later,  Huangbao Yaozhou Kiln and Zhejiang Cixi Yue Kiln followed suit. Since then, underglaze color has been widely popular and has repeatedly created excellent works.

The most typical is blue and white porcelain, which is called "national porcelain" by the world.

At present, ceramic archaeologists generally believe that blue and white porcelain appeared in the Song Dynasty, and some scholars believe that it should be earlier, at least dating back to the late Tang Dynasty.

1983, a batch of specimens considered as blue and white flowers in Tang Dynasty were unearthed at Tang Cheng site in Yangzhou. Unfortunately, there are too few objects and no complete utensils.

However, it was not difficult to fire underglaze blue-and-white porcelain in Song Dynasty.