Ryujin Swords

Koto Katana, Nakajima Rai NBTHK Tokubetsu Hozon

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Period: Nambokucho period (1336-1392).

Mei: Mumei. Attributed to Nakajima Rai at the January 2006 NBTHK Hozon shinsa. Passed Tokubetsu Hozon at NBTHK April 2011 shinsa.

Sugata: Shinogi-zukuri, very shallow tori-zori, iori-mune, bo-hi on both sides ending in kaki-nagashi.

Overall length: 33.19 inches (843.00 mm)

Nagasa: 26.42 inches (671.00 mm) long.

Nakago: O-suriage, 6.77 inches (172.00 mm), kiri-jiri, one mekugi-ana. The yasurime are kiri.

Kissaki: Chu-kissaki, inches (35.60 mm). The boshi tends towards kaen-boshi with short kaeri.

Moto-haba: 1.11 inches (28.20 mm). Moto-gasane: 0.28 inches (7.00 mm). Saki-haba: 0.79 inches (20.00 mm). Saki-gasane: 0.21 inches (5.30 mm).

Sori: 0.34 inches (8.60 mm)

Hamon: A slightly undulating suguha in ko-nie, sunagaeshi especially in the region of the habuchi (the transition zone), plus ko-ashi and gunome ashi in places.

Hada: Itame-mokume, some o-hada, some chikei and abundant ji-nie.

Blade condition: Excellent. Polish by Mishina. No fatal flaws and no cracks. One minor opening, but that's allowed in a blade of this age.


In shirasaya with shingunto koshirae. The shirasaya has a very nice gold-foiled copper habaki.

The original shingunto mounts are in very good condition and quite high quality. The tsuka bears a kashiwa mon which, unlike many others, has not been defaced. The kashiwa mon is associated with the Katsura family, which produced a couple of notable individuals in the 19th century, Kido Takayoshi and Katsura Taro. It is, in short, an ancestral sword that was taken to war by someone proud of their samurai ancestry.

The sword tassel is original to the mounts and denotes either a major or lieutenant colonel.


This sword appears in the To-ken Society's Sword Register.

The Nakajima Rai school was founded by Rai Kuninaga, a pupil of Rai Kunitoshi in Kyoto. Fujishiro, who rates the first Kuninaga as josaku, states that “when viewed from this point, that he is unmistakenly part of the Rai extended family”. The first Kuninaga later moved from Kyoto to Nakajima in Settsu province (Osaka) around the Gentoku period (1329-1331). There seem to be three generations of this name, followed by Munenaga, Yoshifusa and Tomouji.

The main Rai school is representative of Yamashiro-den in the late Kamakura and Nambokucho periods. This sword is not typical of the main Rai school, hence the attribution the the Nakajima Rai school by the NBTHK. A sword of the main Rai school would be expected to have a suguha hamon, but one with more emphasis on nie. Similarly the shape is earlier than expected and the irregular boshi would not be seen in the mainstream Rai school.

A superb sword in superb polish.

£14,000. Free shipping, bag included. Currency conversion.