After the Ōnin War broke the Ashikaga order, a century of Sengoku warfare armed nearly every province in Japan. The era rewards a discriminating eye: routine work exists in quantity, and beside it stand custom blades of the first rank.
This is a tanto by Ko-Gassan with beautiful ayasugi-hada. Gassan works up until the Muromachi period are called Ko-Gassan, and the unique ayasugi-hada grain pattern is magnificent. Although the Hozon Kanteisho states Sadanori, it is the work of Masanori as listed in the Nihonto Meikan. * "Gassan Masanori" Also signs mei as Dewa no Kuni-ju Gassan Masanori, residing in Dewa no Kuni Yachi, a swordsmith around the Eisho era. Yachi, Nishimurayama-gun, Yamagata Prefecture. (From Nihonto Meikan) The workmanship consists of ayasugi-hada with a suguba hamon featuring ko-midare. As Gassan ni-ji mei are usually common, this work featuring an individual mei and a nenkio is also valuable as historical material. Furthermore, the place name Dewa is chiseled, and the fact that it was forged at the Dewa Sanzan, a sacred site for Shugendo, is also precious; it is a commemorative work as historical material for Gassan and, by extension, Japanese religion. <Although difficult to see due to the fine tagane, the first stroke of "Ma" (真) continues long horizontally; the mei is correctly Gassan Masanori, and Sadanori is a misreading.>
Offered by Hyozaemon
35 on the market









As written by the shop
Machine translation from the shop's Japanese · may contain errors ·
Wakimono · Dewa
35 pieces on the market now
Mount Gassan rises among the Dewa Sanzan, the three sacred peaks of northern Japan bound to the mountain asceticism of Shugendō, and the swordsmiths who took the mountain's name worked in its shadow in Ōshū, Dewa Province. The setsumei record that smiths signing "Gassan" are noted in the Kanchiin-bon Meizukushi as early as the Heian period, and the lineage's oldest surviving signed blade is a tachi simply signed Gassan, kept at the Gassan Shrine and judged to date from the late Nanbokuchō to early Muromachi period. Around that same early Nanbokuchō moment the corpus places Gassan Nagamitsu, whose signed tachi answers to the "Ushū Gassan group, around the Ryakuō era" recorded in the Meikan, and Shōgun, a Nanbokuchō hand sometimes identified with Gunshō, dated Genchū 3 (1386). A later branch is carried by Gassan Chikanori, working into the mid and late Muromachi (an ubu wakizashi dated Eishō 9, 1512). The line was revived in Osaka in the closing Tokugawa and Meiji years by Gassan Sadayoshi and his adopted son Gassan Sadakazu, who endured the Haitōrei edict and was appointed Teishitsu Gigei-in (Artist to the Imperial Household) in Meiji 39; his own adopted son Gassan Sadaichi continued the title into Taishō. The forging is the school's signature. " Over the itame base the grain flows (nagare) and tends to stand; ji-nie adheres and chikei enter, and the northern steel takes a dark, metal-like (kana-iro) hue read as Ōshū temperament.
The temper of the old line is a suguha whose nioiguchi is shizumi (subdued), at times mixed with gunome and ko-midare and softened toward urumi, the bōshi turning back in ko-maru. Departures within the corpus mark the lineage's range: Chikanori's late work can drop the ayasugi entirely and absorb Sue-Bizen and Osafune manners, while the Osaka revival smiths command itame with thick ji-nie, flamboyant nie-laden midare, kinsuji, and sunagashi in a full Sōshū idiom, and both Sadakazu and Sadaichi added meticulous horimono, from Bishamonten kurikara to taki kaen Fudō and dragon carvings carved by the same hand that forged the blade. For recognition the setsumei point first to the wave-grain ayasugi and the subdued, often slightly urumi northern nioiguchi, and where these recede, to the dark steel and standing grain that still betray an Ōshū hand. Signed examples of the old line are described as extremely rare, which raises the documentary weight of Nagamitsu's tachi and Shōgun's dated tantō. Provenance threads through the school's own sanctuary: the founding tachi and an Important Art Object tachi both reside at the Dewa Sanzan and Gassan Shrines. The Osaka revival is anchored by Sadaichi tantō signed Teishitsu Gigeiin, recorded in Honma's inventory of the Imperial collection, alongside a Sadakazu wakizashi made on commission for Prince Kuni. Across six centuries the setsumei track a single mountain workshop, from the subdued ayasugi of the Dewa founders through a Muromachi offshoot that turned toward Bizen, to the Imperial-rank carvers of Osaka who reproduced the old wave-grain while mastering the wider traditions. Learn more →
| Smith | Era | Designated |
|---|---|---|
| Tomosada友定 | 1532-1555 | 0 |
| Naonori直則 | 1830-1844 | 0 |
| Toshiyasu俊安 | 1504-1521 | 0 |
| Nagahisa長久 | 1334-1338 | 0 |
| Hisatoshi久利 | 1392-1573 | 0 |
The Muromachi period (1392 to 1573)
After the Ōnin War broke the Ashikaga order, a century of Sengoku warfare armed nearly every province in Japan. The era rewards a discriminating eye: routine work exists in quantity, and beside it stand custom blades of the first rank.
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 siteWithin one week of the item's arrival (cooling-off is available within Japan only). If the returned item's condition differs from the time of sale, or the item has been used, no refund can be given. For defects that differ from the purchase conditions, we accept the return and refund the payment. (A defect means something that impairs the item's proper use, such as a hagire (crack in the edge), a re-tempered blade (saiba) or a forgery; items described as having a hagire, a saiba or as a forgery are excluded.) For overseas customers, please consult us separately.
¥880,000