Japanese Katana, signed Bishū Osafune Sukesada (備州長船祐定作), dated Eiroku 8 (1565) — late Muromachi period, Bizen — NBTHK Hozon Tōken — ubu, dated, with a period koshirae and a shirasaya

Ubu, signed-and-dated Sengoku-era Bizen Osafune Sukesada katana · well-packed itame with the faint midare-utsuri that is the hallmark of Bizen · notare-based suguha with ko-gunome, ashi, yō and ko-nie · a deep 2.2 cm sori · NBTHK Hozon, complete with both a period mounting and a shirasaya

An NBTHK (Nihon Bijutsu Tōken Hozon Kyōkai) Hozon Tōken — its certificate the proof of both assured quality and historical value. This is a superb ubu (original-length), signed (zaimei) katana by Bishū Osafune Sukesada, a master of Bizen working in the late Muromachi period. A precious historical document carrying an Eiroku-era date (1565) cut on the reverse — from the very height of the Warring States (Sengoku) age — it is nonetheless freshly polished, nearly flawless, and exceptionally sound in both ground and edge. Its deep, beautiful 2.2 cm curvature and thick, substantial build preserve the shape of the period exactly as it was, boasting overwhelming beauty and impact.

Highlights for the collector

• Signed and dated: ubu, unaltered tang signed "Bishū Osafune Sukesada" with an Eiroku 8 (1565) date — a true reference piece from the Sengoku period.
• NBTHK Hozon Tōken (No. 383044) — independently authenticated.
• Classic Bizen work: well-forged itame with the coveted faint midare-utsuri, and a lively temper full of ashi and yō.
• Remarkably healthy for its age and freshly polished.
• Complete package: comes both in a flavorful antique koshirae for display and in a shirasaya for safe storage.

Workmanship and condition

Freshly polished, the blade is in extremely sound condition wholly worthy of the Hozon designation; in the interest of full disclosure, a few flaws and the trace of a forging blister (fukure) have been filled with patch metal (umegane). The jigane is an itame-hada, exceptionally well forged and packed, across which the faint midare-utsuri (undulating temper reflection) that is the very essence of Bizen rises in wavering form, moist and clear. The hamon is a notare-tinged suguha, breaking into ko-gunome around the monouchi (striking area). Within the edge run abundant ashi and yō, with ko-nie that make it bright and clear. The bōshi turns in as a midare-komi and returns firmly, without a single flaw. The tang (nakago) is ubu and unaltered, clearly cut on the front (omote) with the signature Bishū Osafune Sukesada and on the reverse (ura) with the Eiroku date — carrying the weight of history to the present day.

Form

The sori stands deep at 2.2 cm, and both motohaba and sakihaba are solid, giving a thick, substantial build. The blade perfectly preserves the form of a sword of the late-Muromachi age of war, and the weight and dignified bearing felt when it is taken in hand are truly in a class of their own.

On the smith — Bishū Osafune Sukesada

The Osafune school of Bizen province has been called the very "incarnation of the swordsmith," the single most prosperous lineage in the entire history of the Japanese sword. Among them, the Sukesada line that rose to fame in the late Muromachi period were masters who perfectly fused practicality and beauty, winning overwhelming support from warlords throughout the country. Blades like this one — meeting the harsh demand of the Sengoku era yet made with the very highest technique, and surviving in ubu, signed, and healthy condition — are exceedingly rare today, and are highly prized as emblematic of the beauty of Bizen swords.

The period koshirae

The sword is accompanied by a fine jidai koshirae of aged dignity and quiet composure. The hilt is finished in subdued brown cord wrap, and a round iron tsuba — pierced with a fine chrysanthemum-and-vine openwork against a subdued iron ground — provides an exquisite accent, evoking the refined aesthetic of the samurai. The black-lacquer saya retains an age-appropriate character, and the ensemble as a whole is in very good condition. In addition, a shirasaya for protection and storage is included (with a small chip to part of the horn).

A fine sword combining an Eiroku-dated ubu form that breathes the very air of the Sengoku era with an almost miraculous, near-flawless soundness. With its NBTHK Hozon certificate, a beautiful blade in which one can savor the essence of Sukesada, and a characterful period koshirae, it is a piece fully worthy of heading any collection.

Specifications

• Type: Katana (shinogi-zukuri)
• Signature (mei): Bishū Osafune Sukesada (備州長船祐定作), front; dated Eiroku 8 (1565), reverse; ubu, zaimei
• Certification: NBTHK Hozon Tōken (No. 383044), issued May 28, 2019
• Period: Late Muromachi period, dated Eiroku 8 (1565)
• Smith / school: Bishū Osafune Sukesada — Bizen Osafune school
• Jigane: well-packed itame with faint midare-utsuri; moist and clear
• Hamon: notare-based suguha with ko-gunome at the monouchi; abundant ashi and yō, ko-nie, bright and clear
• Bōshi: midare-komi, returning firmly
• Blade length (nagasa): 68.4 cm / 26.93 in (2 shaku 2 sun 6 bu)
• Curvature (sori): 2.2 cm (deep)
• Width at base (motohaba): 33.9 mm
• Thickness at base (motokasane): 7.3 mm
• Width at tip (sakihaba): 22.9 mm
• Thickness at tip (sakikasane): 5.4 mm
• Weight (blade only): 890 g
• Weight (without scabbard): 1,180 g
• Condition: freshly polished, very sound; a few flaws and a forging-blister trace filled with umegane; ji and ha healthy
• Mounting: period koshirae — brown-wrapped tsuka, round iron tsuba with chrysanthemum-and-vine openwork, black-lacquer saya; shirasaya also included (minor horn chip)
• Torokushō (Japanese registration) No.: Kōchi 33348