This is an unsigned (mumei) Japanese katana dating to the Koto period (pre-1596). The blade measures 66.2 cm in length with a 1.5 cm sori. It has been ō-suriage (greatly shortened) and retains three mekugi-ana, bearing witness to centuries of remounting and continued preservation. The elegant suguha hamon gives the sword a refined and dignified appearance characteristic of classical Japanese workmanship.
The koshirae is a genuine Imperial Japanese Navy Kaigunto mounting, fitted with a distinctive black lacquered scabbard finished in a diagonal ribbed pattern. This textured lacquer style is a rare variation found on naval officer scabbards.
A fine historical example combining the craftsmanship of a Koto-period blade with the distinctive elegance of Imperial Japanese Navy officer mounts, making it an excellent addition to any serious Nihontō or military sword collection.