Proto-celadon (Chinese: 灰釉陶, also 原始青瓷) was a type of Chinese ceramic which developed during the Shang period and Western Han periods. It is often qualified as "proto-porcelain", and was usually adorned with a light yellowish green glaze.
The body of proto-celadon was made of porcelain clay, with an iron content below 3%. Firing temperature was around 1200 degreed Celsius. Surface treatment consisted in a lime glaze. The type of objects manufactured in proto-celadon were similar to the objects manufactured in bronze.
Inception of true celadon
From the Eastern Han period, true celadon ware (Chinese: 成熟青瓷) started to appear, with production focused on the Zhejiang Province. Although still following the shapes and patterns of proto-celadon wares, these advances now represented the characteristics of true porcelain, with refined and pure clays and correct firing temperatures.
- A Handbook of Chinese Ceramics from The Metropolitan Museum of Art