A fine unsigned Japanese blade mounted in an Imperial Japanese Navy officer’s Kaigunto koshirae.
The blade measures 59.6 cm in nagasa and shows a tight itame-hada with a mostly straight suguha hamon displaying subtle nie activity. The kissaki is of medium length, and the nakago bears a single mekugi-ana with natural patina consistent with age.
The workmanship suggests Edo-period tradition, likely influenced by the Bizen or Mino schools, later remounted for military use during the early Shōwa era. The Naval koshirae remains in excellent condition, with well-preserved sharkskin-covered scabbard and metal fittings retaining much of their original finish.