This is a Ko-Imari soba choko, a small bowl with underglaze blue decoration. Perhaps it's a cylindrical bowl? It can be used as a soba choko, and it's a wonderful piece that can be used for various purposes. I've kept it carefully in its box for many years, but I've decided to sell the complete pieces separately from those that aren't. Both of these are complete, and I think they have a very rare and wonderful atmosphere. Approximately 9.3cm in diameter x 6.5cm in height.