Ohira Uchigumori Rare Japanese Natural Finishing Whetstone

This exceptional Japanese whetstone was selected by us and imported directly from Japan, thoroughly tested and sealed on sides and back to protect the stone for long term use.

It measures 206 mm (8.11 inches) long × 70 mm (2.76 inches) wide × 25 mm (0.98 inches) tall, and weighs 848 g (29.90 oz / 1.87 lbs).

Hardness: 4.4
Old stock Ohira Uchigumori which was sourced directly from the late miner of Ohira. This Uchigumori is fine and firm with clean, classic blue base with dense Aka renge. There are areas of orange Yaki which seem to be waiting for further use/lapping. Uchigumori is mined from the Tenjou Suita layer and similar to all strata and mines, they vary in characteristics. The surface is flat and ready to use with the backside remaining chiseled. The side of the stone is stamped as well. The stamps on the face/side read; "Ohirayama" & "Uchigumori". A fine, firm Uchigumori capable of finishing very fine and bright. This particular stone is quite hard and perfect for a wide of applications including razor finishing, knives, tools and sword polishing. The stone has zero impurities or lines. This Uchigumori is densely composed of fine abrasive particles which act when sharpening with water only. Very little to no self slurry is released when sharpening a Kanna blade. Inky black swarf is indicative of the high abrasive content. Even further, when slurry is forced, the abrasive is released, and the stone starts cutting extremely fast. This stone is unique in that the firm base allows for refinement characteristics which are not available in softer Uchigumori. This results in a unique, deep, reflective polish. These Ohira Suita from this particular wholesalers are becoming extremely rare as the owner has recently passed away. Collector Grade Stone!

A photo of the stone's polishing ability on soft and hard steels of a Japanese kanna (wood plane) blade are shown.