This is an Akama inkstone. I received it from the president of a business partner a long time ago, who explained that it was a valuable inkstone. However, I never used it and it has been stored for many years. I am selling it now because I am planning to move. My name and the sender's name are engraved on the back. I do not know the maker of the inkstone or anything else about it. I heard that it was expensive, so I've started the bidding at 50,000 yen, but if anyone knows more about it, please let me know.