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 blade was signed by Gassan Sadayoshi (月山貞吉) in Feb, the 4th year of the Ka-Ei era(1851). Gassan Sadayoshi’s real name is Gassan Yahachiro. He was born in Dewakoku(Yamagata prefecture today) in 1781. Gassan is the name of the school he belonged to. It was initially founded during the Heian period(late 12th century). It is said that the school name “Gassan” (月山) came from the fact that they forged swords near the mountain called Gassan in Dewakoku. In Sadayoshi’s early career, he learned sword forging technique from his father, Okuyama Yasaburo Sadachika(山弥三郎貞近), who is said to have been a descendant of a member of O-Shu Gassan school (奥州月山), one of the oldest Gassan schools. When Sadayoshi became about 20 years old, he went to Edo city(today’s Tokyo) to serve Suishinshi Masahide(水心子正秀) as an apprentice. Sushinshi Masahide is known as one of the most skilled and famous swordsmiths at the end of the Edo period(150-200 years ago). After ten years of apprenticeship under Masahide, Sadayoshi mastered excellent craftsmanship. And he moved to Osaka in 1833 when he was 30 years old. He founded Osaka Gassan school there, improving his sword-forging technique even more and eventually settled there. He also trained many apprentices, who later became notable swordsmiths at the end of the Edo period. While Gassan school was known as one of the most prestigious schools from the Kamakura period(late 12th century), its presence faded in the early-mid Edo period. However, after Sadayoshi became a highly-regarded swordsmith at the end of the Edo period, the whole school revitalized and flourished again because of his continuous effort. Sadayoshi adopted a son from Tsukamoto family and named him Sadakazu, who later became one of the most famous swordsmiths in the post Samurai period(Meiji era). Father and son spent many years researching traditional Gassan style swords and finally made Ayasugihada, the signature design of Gassan school. Ayasguhihada looks undulating grain pattern in the Jihada(steel surface), which resembles a Japanese cedar grain. Gassan Sadayoshi also forged other styles of swords aside from Ayasugi Hada Jihada. Gassan Sadayoshi died at the age of 71 in the third year of the Meiji era(1870). His son, Sadakazu, preserved the tradition of Gassan, and he passed it down to Sadakatsu. The Gassan school has been running for the 6th generation. The current Gassan alive is Gassan Kazutoshi, and his son is Gassan Sadanobu. They still keep forging traditional Japanese swords in Nara prefecture today. It is appraised as a Hozon Token (保存刀剣) issued by NBTHK (Nihon Bijutsu Touken Hozon Kyokai: 日本美術刀剣保存協会). Authentication Paper They authenticated the blade on March 16th in the 58th year of Showa (1983). They appraised it as Hozon Touken, the blade especially worth preserving for Japanese society. Registration Number It is called Jyu Ho Token Rui Torokusho (銃砲刀剣類登録証).
Offered by Samurai Museum
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Shinshinto · Settsu · around 1830-1863
Fujishiro Jo saku · Tōken Taikan top 49%
1 piece on the market now
Shinshinto · Settsu
28 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 |
Bakumatsu: the last war market
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.
Certifies a genuine blade worth preserving: a signature confirmed correct, or, if unsigned, an era, province, and school that the NBTHK can reliably identify.
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 siteReturns/exchanges limited to defects caused by shipping (except willful misconduct or gross negligence by the company); customers must contact within 72 hours of receiving the product.