What are the characteristics of China's Western Han Dynasty primitive porcelain decoration?

The decorative art of primitive porcelain in the Western Han Dynasty, roughly speaking, the early stage is relatively simple, generally decorated with simple string or water wave pattern, not see the complex decorative patterns. To the middle of the Western Han Dynasty and thereafter, there is a simple engraved pattern, especially the trumpet mouth pots and long-necked pots and other artifacts, often in the artifacts of the mouth rim, the neck, the shoulders and the upper abdomen and other parts of the eye-catching convex strings within the interval of the band, respectively, scratched with the water waves, curly grass, clouds and herringbone pattern. Cloudy lines are soft and smooth, so that people feel like floating clouds, often with beasts and birds between the clouds, the picture is very vivid and beautiful, comparable to the same period of copper and lacquer patterns.