Perry’s arrival in 1853 unraveled the Tokugawa peace and created the first mass demand for working swords in two centuries. Kiyomaro, called the Masamune of Yotsuya, died on its eve; Munetsugu and Yukihide carried the boom to the end.
This is a Gassan school tanto made by Kenryushi Sadaharu, dated to 1868 AD. It features a hira-zukuri shape with sugu-ha hamon and comes in a rare koshirae. The blade is accompanied by an NBTHK Tokubetsu Hozon certificate.
Gassan · Keio (1865-1868)












Shinshinto · Settsu · around 1865-1868
Tōken Taikan top 95%
7 pieces on the market now
Shinshinto · Settsu
41 pieces on the market now
| Smith | Era | Designated |
|---|---|---|
| Sadaharu貞晴 | 1865-1868 | 0 |
| Sadayoshi貞吉 | 1926-1989 | 0 |
| Yoshiaki吉明 | 1844-1848 | 0 |
| Naonobu直信 | 1854-1860 | 0 |
| Sadayoshi貞吉 | 1830-1863 | 0 |
Perry’s arrival in 1853 unraveled the Tokugawa peace and created the first mass demand for working swords in two centuries. Kiyomaro, called the Masamune of Yotsuya, died on its eve; Munetsugu and Yukihide carried the boom to the end.
A Hozon-certified blade judged to show notably superior workmanship and a better state of preservation. The bar is higher: re-tempered blades and most unsigned Muromachi/Edo works are excluded.
The NBTHK (Nihon Bijutsu Tōken Hozon Kyōkai, the Society for the Preservation of Japanese Art Swords) is a public-interest incorporated foundation founded in 1948 and supervised by Japan’s Agency for Cultural Affairs (Bunkachō); it is based at the Japanese Sword Museum in Tokyo. Its expert panels physically examine each submitted work (shinsa) and issue a certificate (kanteishō) ranking it by artistic and historical merit. NBTHK papers are the most widely recognized standard of authentication for Japanese swords and fittings.
NBTHK official siteIf the item fails to meet the description, it may be eligible for a return (at the seller's discretion). Item(s) must be shipped back only via FedEx or UPS within 48 hours of receipt, in original undamaged state. Costs are the purchaser's responsibility.
This is a Gassan school tanto made by Kenryushi Sadaharu, dated to 1868 AD. It features a hira-zukuri shape with sugu-ha hamon and comes in a rare koshirae. The blade is accompanied by an NBTHK Tokubetsu Hozon certificate.
Gassan · Keio (1865-1868)












Shinshinto · Settsu · around 1865-1868
Tōken Taikan top 95%
7 pieces on the market now
Shinshinto · Settsu
41 pieces on the market now
| Smith | Era | Designated |
|---|---|---|
| Sadaharu貞晴 | 1865-1868 | 0 |
| Sadayoshi貞吉 | 1926-1989 | 0 |
| Yoshiaki吉明 | 1844-1848 | 0 |
| Naonobu直信 | 1854-1860 | 0 |
| Sadayoshi貞吉 | 1830-1863 | 0 |
Perry’s arrival in 1853 unraveled the Tokugawa peace and created the first mass demand for working swords in two centuries. Kiyomaro, called the Masamune of Yotsuya, died on its eve; Munetsugu and Yukihide carried the boom to the end.
A Hozon-certified blade judged to show notably superior workmanship and a better state of preservation. The bar is higher: re-tempered blades and most unsigned Muromachi/Edo works are excluded.
The NBTHK (Nihon Bijutsu Tōken Hozon Kyōkai, the Society for the Preservation of Japanese Art Swords) is a public-interest incorporated foundation founded in 1948 and supervised by Japan’s Agency for Cultural Affairs (Bunkachō); it is based at the Japanese Sword Museum in Tokyo. Its expert panels physically examine each submitted work (shinsa) and issue a certificate (kanteishō) ranking it by artistic and historical merit. NBTHK papers are the most widely recognized standard of authentication for Japanese swords and fittings.
NBTHK official siteIf the item fails to meet the description, it may be eligible for a return (at the seller's discretion). Item(s) must be shipped back only via FedEx or UPS within 48 hours of receipt, in original undamaged state. Costs are the purchaser's responsibility.