Nihonto Katana "Osafune Sukemori" Kanteisho certificate

Description

ITEM DESCRIPTION:

Comes with kimono or cotton bag. Comes with certificate of supein Nihonto. Comes with copy of Tokosusho. Comes with 日本刀剣保存会 Kanteisho.

Documentation

• Certificate and registration

  Document: 鑑定書 (Kanteisho)

  • “Kanteisho (certificate): Sword (katana).
    Signature: ‘Sukemori, resident of Osafune, Bizen Province.’
    Date: second month of Bunka 5 (1808).
    Blade length: 69,7 cm. Curvature: 13 mm.
    It is hereby certified that the above is genuine.
    Certificate date: 18 September, Reiwa 7 (2025).
    Organization: Juho Token Kenkyūkai.
    Examining committee signature: Tsujimoto Masayuki.”

  • “Construction: shinogi-zukuri, iori-mune.
    Jihada: ko-itame.
    Hamon: suguha.
    Nakago: ubu, one mekugi-ana.
    Period/era: Bunka.
    Lineage/school: Osafune.”

  • “Commentary: Son of Ise no Kami Sukemori; later known as Shichibee Sukemori. This work uses well-forged ko-itame jigane and skillfully tempers a suguha. A genuine blade with ubu nakago and signature.”

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  Smith, school, and historical framework

  The blade is signed 備前國長船住祐盛 (Bizen no Kuni Osafune jū Sukemori) and dated 文化五年二月 (second month of Bunka 5, 1808), therefore Edo period. The certificate itself provides the key biographical note: Sukemori is stated to be the son of Ise no Kami Sukemori, and to have later adopted the name Shichibee Sukemori. The lineage/work tradition is recorded as 長船 (Osafune).

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  Technical description of the blade

  A katana with nagasa 69.7 cm and sori 1.3 cm, made in shinogi-zukuri with iori-mune (per the certificate). The jigane is specified as ko-itame, and the hamon as suguha—a restrained, classical approach that emphasizes a clean line and confident heat-control. The kissaki is of medium proportions, with a controlled point-treatment consistent with a straight-temper concept and a tidy transition at the tip.

  The nakago is described as ubu (生茎) with one mekugi-ana (穴一); the blade is signed (zaimei) with the signature stated above, and the document explicitly certifies it as genuine.

  Overall, the photographs present the blade in a well-kept, readable condition, with a clear profile and good visual contrast along the ha.

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  Shirasaya and fittings

  The sword is housed in a plain wooden shirasaya, closely fitted to the blade’s outline—an optimal preservation mount: stable protection for the steel, minimal contact/friction, and a deliberately understated aesthetic that keeps the focus on the blade itself.

  The habaki is a white-metal example, with one face finished in a granular/ishime-like texture and the other in a smooth finish—an elegant, functional pairing designed for secure seating at the shirasaya mouth and safe handling.

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  Specifications

  Type: Katana
  Signature (mei): 備前國長船住祐盛
  Date on blade: 文化五年二月 (1808, 2nd month)
  Period: Edo
  School/lineage (per certificate): 長船 (Osafune)
  Nagasa: 69.7 cm
  Sori: 1.3 cm
  Construction: 鎬造・庵棟 (shinogi-zukuri, iori-mune)
  Hamon: 直刃 (suguha)
  Jihada: 小板目 (ko-itame)
  Nakago: 生茎・穴一 (ubu, one mekugi-ana)
  Mount: Shirasaya
  Habaki: white metal; one face ishime-textured, the other smooth