Abstract
The morphology and microtopography of hydrothermal illite in the Izumiyama pottery stone, Saga Prefecture, Japan, have been examined by atomic force microscopy. Izumiyama hydrothermal illite particles in the high alteration part have polygonal to lath-shapes and tend to be thick. On the other hand, illite particles in the lower alteration part show circular or malformed circular ones. The two samples also show different crystal growth patterns. We report the differences in morphology and microtopography between the two samples and discuss on the crystal growth mechanism of them.