I purchased this at a pottery fair in Saga Prefecture about 20 years ago. It's a corner chopstick rest from Ippogama. It can be used as a chopstick rest or as a small dish for appetizers. The black stain in the upper right of the blue piece (in the fourth photo) has been there since I bought it. I've used it about twice. It has been stored at home and has some minor stains on the back. I will wrap it in cushioning material and send it via Yu-Packet Post Mini.