A fine koto katana in the Gassan tradition. Classic ayasugi hada can be seen the entire length of the blade and ji-nie appears on the hada. The suguha hamon is frosted in glowing nioi with ko-nie. The boshi is ko-maru shape with nice hakikake (similar to sunagashi, but with thinner lines resembling brush strokes).

Gassan is the name of a mountain in Unshu (Dewa) where the school originally started. The distinctive kantei point for the Gassan school is Ayasugi hada (beautiful undulating waves that create uchinoke as they cross into and out of the hamon). The secret to this was the heating of the sword at low temperatures which helps prevent the blade from being brittle and therefore breaking in combat. Low temperature yaki-iri was best suited for the production of suguha on strong ayasugi and masame hada. These swords were quenched using water from Mount Gassan.

In the koto times, most Gassan smiths signed with their school name only or with no signature at all (mumei) and so the names of the individual smiths are mostly lost to time. It is known that the Gassan supplied swords to the famous warrior monks of Dewa province (Shugendou) and did not sign their swords out of respect.

For some reason the school died out at the end of the Muromachi period. There is much speculation about why this occurred. Some say that it was due to the demise of the warrior monks while others say it was due to the Oe and Shiratori, the major patrons of the Gassan school, being destroyed by the vying military power of the Mogami in Tensho 12 (1584). It is interesting to note that the school was revived again by Gassan Sadayoshi in the early 1800’s. Sadayoshi studied under the famous shinshinto smith Suishinshi Masahide and set up his school in Osaka. This line is therefore known as Osaka Gassan while the original school is known as Ko Gassan or Dewa Gassan.

This katana dates to the Muromachi period (1392-1573) and bears all the hallmarks of the Ko Gassan tradition including ayasugi hada and narrow suguha hamon. It is mumei (unsigned) and the nakago is in beautiful unaltered condition. This sword has a nice graceful feeling reminiscent of koto times and the jigane is suprisingly tight for Ko Gassan.

This katana was recently awarded NBTHK Hozon papers and with its ubu condition with one mekugi-ana it makes a nice representative piece of the Gassan school for a collector to own. It is also accompanied by a very nice koshirae from the Edo period.




School: Dewa no Gassan
Paper: NBTHK Hozon
Period: Muromachi period (1392-1573)
Fujishiro Ranking: Chu jo saku (above average quality)
Mei: Mumei
Form: Katana
Sugata: Shinogi-zukuri
Nagasa: 66.3 cm
Sori: Torii
Sori measurement: 10.5 mm
Mune: Iori
Kasane (thickness): 6.4 mm
Width at ha-machi: 28.6 mm
Width at yokote: 20.7 mm
Nakago condition: Ubu
Nakago shape: Standard with kuri jiri
Nakago length: 18.7 cm
Mekugiana: One
Yarurime: Sujikai


The stunning koshirae features olive coloured string wrapping and a black lacquered saya. The shakudo fuchi kashira features a design of clematis flowers and vines in gold and looks to be the work of Waki-Goto. The menuki feature mandarin trees in snow and I suspect they are mainline Goto (perhaps Kenjo). The tsuba is by the Akasaka school and features a design of tokei (clock gear). This tokei design has also been referred to as a Christian or Jesuit motive. Please see Fred Geyer’s excellent article about this in the 2nd edition of the Kokusai Tosogu Kai (KTK) convention and exhibition catalogue. The old same (rayskin) is striking in contrast to the string wrap. A true high end mounting to fit this wonderful koto sword.

This fine sword comes in polish, shirasaya, tsunagi with mounts and papers.


May 2012

Additional photos can be found here – http://www.nihontoantiques.com/fss414.htm. Please note that I have changed the tsuba to something more suitable.