Sagami Province, Azuchi-Momoyama Period, circa 1592
Certificate: Nihon Bijutsu Token Hozon Kyokai (NBTHK), Tokubetsu Hozon Token
Overall Length: Blade 37.7cm; Koshirae (mount) approx. 58cm
Era/Location: Sagami (Kanagawa Prefecture), attributed 1592 onward

Nagasa (Cutting Edge): 37.7cm
Sori (Curvature): 0.4cm
Moto-Haba (Width at Base): 3.35cm
Moto-Kasane (Thickness at Base): 0.65cm
Saki-Haba (Width at Tip): 2.95cm
Saki-Kasane (Thickness at Tip): 0.50cm
Habaki: Two-part, gold-foil
Nakago (Tang): Unaltered, with kiriyasuri file marks; 1 mekugiana (rivet hole)
Tsukurikomi (Shape): Hirazukuri, Mitsumune
Registration: Tokyo Prefecture

Blade Characteristics
The jigane reveals a sophisticated mix of itame-hada and mokume-hada, shimmering with prominent jinie. Hamon in notare and gunome-choji-midare patterns display fine konie, with activity throughout including visible ashi, ha, sunagashi, and kin-suji. Boshi executed with hakikake and komaru, sweeping elegantly to a compact tip. The tang is ubu (unaltered), finely preserved with superb, crisp kiriyasuri file pattern and rich, consistent patination.

Historical Attribution
Attributed to the third generation Tsunahiro, Yamamura Soemon, resident of Ogigadani, Kamakura and later Hirosaki by invitation of the Tsugaru lord. He is credited with producing over 300 swords, with his family’s lineage continuing for fifteen generations into Meiji and Taisho periods. Tsunahiro III’s swords distinguish themselves through robust construction, exceptional sharpness, and fine aesthetic qualities, considered late-period masterpieces of the Sagami tradition.

Koshirae and Mounting
Koshirae length measures approx. 58cm. The habaki is double gold-foiled, reflecting period luxury.

Provenance & Certification
Accompanied by NBTHK Tokubetsu Hozon Token certificate, verifying its authenticity, artistry, and historical significance as a work of special preservation by the foremost sword authority in Japan.

Scholarly Note
The present blade reflects the mature artistry of Tsunahiro III, embodying hallmark features of his school: a firm and elegant profile, actively patterned steel, and powerful, beautifully controlled temper. The sword’s provenance, technical accomplishment, and official NBTHK certification confirm its stature among the finest Azuchi-Momoyama tanto from Sagami.