Seven samples from Chenghua reign have been investigated. Here we show the results from two samples. One sample is a lid of box with diameter 25cm.
The other sample is a bowl with diameter 16cm, and height 6,5cm.
With naked eyes, the iron spot from shard samples of Chenghua reign are not obvious. Only a few iron spots can be observed, which indicates that the fine cobalt pigment had been gently executed during this period.
1 microstructure of iron spots
Photos of iron spots from lid 016.
Photos of iron spots from bowl 024.
As on the samples from Xuande period, there are two types of crystal can be seen: red-brown crystal and grey crystal. These two types crystals appear together almost all the time. It seems that the grey crystals grow above the red-brown crystal. Moreover, the red-brown crystal is imbedded in the glaze. While the grey crystal is formed directly above the red-brown crystal and on the most surface of the glaze, just like those samples from former period (Hongwu and Xuande).
2 glaze on the surface
