This is a vintage Amakusa whetstone from an earlier generation, clearly distinct from the Amakusa stones commonly found on the market today.

The stone features a warm ivory-colored base with the characteristic brownish linear patterns unique to Amakusa stone. This beautiful appearance is rarely seen in more recently quarried Amakusa stones, giving it the distinctive character and charm associated with older vintage material.

The estimated grit is #2,000+, though in practical use it performs closer to a #3,000 grit stone. Its structure is exceptionally fine and dense, providing a smooth, silky sharpening feel. During sharpening, it develops a light, blackish slurry that remains clean and easy to control. Despite its refined feel, the stone offers excellent cutting performance, making it suitable not only for the medium sharpening stage of kitchen knives but also for the Binsui stage of traditional Japanese sword polishing.

Throughout sharpening, the abrasive particles work consistently and evenly, allowing the edge to be refined with excellent control while delivering the satisfying feedback that only a high-quality natural whetstone can provide. It also serves as an outstanding transition stone before moving on to a natural finishing stone (Awasedo).

Vintage Amakusa stones of this quality and age rarely appear on the market today. As such, this stone is valuable not only as a practical sharpening tool but also as a highly collectible natural whetstone.

Combining outstanding sharpening performance with the rarity and historical character preserved through the decades, this is a remarkable piece that will appeal equally to dedicated sharpeners and serious collectors.

Please note that these are not for beginner sharpeners since they're harder to use.These are natural stones meaning that every single one of them are different so my measured size are not accurate. This is a life time investment for people who lives sharpening their knives and tools, do not hesitate to ask me your questions.