This is a natural finishing whetstone from Shoubudani, Kyoto, bearing the historic designation "Gosenryo" (五千両).

Shoubudani is regarded as one of Kyoto's most respected natural whetstone-producing areas, alongside famous regions such as Nakayama and Okudo. For generations, it has produced high-quality finishing stones used for sharpening swords, kitchen knives, planes, chisels, and a wide variety of edged tools.

The name "Gosenryo" is relatively well known among Japanese natural whetstone enthusiasts. However, unlike geological layer names such as Tomae, Suita, or Asagi, "Gosenryo" is generally believed to be the name of a quarry section, a trade name, or a traditional designation rather than a specific geological stratum. Although surviving historical records are limited, names such as "Shoubudani," "Choushirou," "Ushike," and "Gosenryo" are often mentioned together by veteran Kyoto whetstone dealers and collectors.

Some collectors believe that "Gosenryo" referred to a specific quarry face associated with the Choushirou workings, while others interpret it as a designation reserved for particularly high-grade stones produced from the Choushirou area. Because detailed quarry records no longer exist, neither theory can be conclusively verified. Nevertheless, the name has long been associated with high-quality Shoubudani stones.

One popular explanation for the origin of the name is that the stones produced there were considered valuable enough to be worth "five thousand ryo," a substantial fortune in old Japan. From the Edo period through the early Showa era, mines and quarry sites were often given auspicious names such as "Senryo" (One Thousand Ryo), "Manryo" (Ten Thousand Ryo), and "Hozan" (Treasure Mountain). "Gosenryo" is thought to follow this tradition.

This particular stone was acquired from a Japanese natural whetstone collector and is believed to originate from the Aisa layer. During sharpening tests, it exhibited a pleasant degree of cushioning along with a soft and gentle sharpening feel. A delicate gray slurry was continuously generated, allowing the blade to glide smoothly across the surface while producing a refined and natural kasumi finish. Another noteworthy characteristic is its excellent slurry and swarf management. Sharpening residue is released exceptionally well, helping to prevent the surface from loading up during use.

In recent years, high-quality Shoubudani stones have become increasingly difficult to obtain, and opportunities to acquire examples bearing the historic "Gosenryo" designation are even rarer. As a result, this piece is appealing not only as a practical sharpening stone but also as a collector's item that preserves an important part of Kyoto's natural whetstone history and culture.

Overall, this is a fine natural whetstone that combines refined sharpening performance with excellent practicality and ease of use.

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 sizes are not accurate. This is a lifetime investment for people who live sharpening their knives and tools, do not hesitate to ask me your questions.”

Dimension : 55-85mm×140-155mm×31mm ( Approx.) 

Weight: 967g