This is from quite a while ago, when I helped clean up a woodworking factory as a craftsman was retiring. I received several natural whetstones at that time. I also use whetstones in my work, but I've found artificial whetstones to be sufficient, so I've had this one unused for a long time. I've decided to put it up for sale now. Length: Approximately 19 cm Width: Approximately 6.8 cm Thickness: Approximately 2.5 - 2.7 cm Weight: Approximately 0.9 kg I'm not very knowledgeable about natural whetstones, so I may not be able to answer difficult questions. Please judge the details based on the photos. The photos in the latter half show the stone when wet. Thank you.