When a railway was under construction in 1899, many pieces of exquisite pottery were unearthed from tombs of the Tang Dynasty near Luoyang, Henan Province. The pieces of pottery were in yellow, green and white colours or in yellow, green and brown colours. Since they were unearthed from tombs of the Tang Dynasty, they were called "Tang tri－coloured glazed pottery".
The production of glazed pottery in China dates back to ancient times. Single－colour glazed pottery appeared during the Han Dynasty. Fine glazed pottery was made during the Tang Dynasty. The craftsmen mastered metallic oxide property and colouring mechanism. They applied glaze of different colours to a single article, creating the Tang tri－coloured glazed pottery with unique artistic effects.
The base of pottery was made of kaolin, a kind of fine clay. After the base was shaped and dried by airing, it was baked in a kiln. Then the base was glazed and baked in the kiln again. Minerals of different metallic elements were mixed with glaze. With lead as a flux, the glaze was applied to the surface of the base. When the base was baked, the metallic oxides of different colours melted in the glaze and spread around.
The various colours of glaze appeared with the interaction of different metallic elements. Copper, iron, manganese and cobalt elements showed green, yellow, purple and blue colours separately. The difference in the content of various metallic elements also showed different colours. All this brought about a great variety of magnificent glaze.
Coloured glaze was usually not applied to the head of a pottery figurine. After the base was baked, a few touches of Chinese ink were painted to feature the eyes, eyebrows and beard. The facial expression and inner world of a figurine were portrayed most vividly.
Tang tri－coloured glazed pottery was baked in the kiln at a low temperature. It was fragile and not well watertight. So it was far inferior to porcelainin practical value. What we see today are pieces of Tang tri－coloured glazed pottery used as burial objects. Lavish funerals prevailed during the Tang Dynasty. Exquisite pieces of tri－coloured glazed pottery were burial objects favoured by the nobility and the common people.
There are a great variety of Tang tri－coloured glazed pottery pieces. With unique shapes, they had the rich flavour of life. They covered almost every field of life related to the dead, from models of architecture to plates, bowls and other articles of everyday use, from horses, carriages to toys, from figurines of beautiful noble ladies to those of the heavenly kings with a fiery temper. They displayed the colourful social life and the splendid culture of the Tang Dynasty.
When we wipe the thick dirt from the Tang tri－coloured glazed pottery, we can see the gorgeous glaze colour. What they display is a picture scroll of the colourful social life during the Tang Dynasty.