This is a natural whetstone of unknown origin. Size: 80 x 210 x 45 mm, Weight: 1786g Purchased from a carpenter's tool shop in Niigata for about 100,000 yen. The finish is a mirror-like finish, resulting in a mirror-like finish even on the jigane (steel). It's a hard whetstone. There is a possibility of layer cracking or vertical cracking, so it has been thickly coated with cashew lacquer. There are streaks, but they are not harmful at the moment. If you are concerned, you can dig them out. I liked using it, but I am selling it due to a lack of funds. Thank you.