Katana, unsigned, attributed to Sadamune (Owari Tokugawa family transmission)

Sadamune (commonly known as Hikoshiro) was a swordsmith active in Sagami Province (present-day Kanagawa Prefecture) from the late Kamakura through the early Nanbokucho period. Said to be either the son or adopted heir of Masamune, the perfecter of the Soshu tradition, he held the rank of Sahyoe-no-jo. Inheriting Masamune's style, he produced works noted for their brilliant steel and vigorous hamon.

This katana measures 69.1 cm in blade length with a curvature of 2.4 cm. It is an o-suriage (greatly shortened), unsigned blade that retains the wide, imposing form typical of the Nanbokucho style. The steel shows ko-itame grain with chikei, while the hamon is a notare pattern richly threaded with ashi, interlaced with kinsuji and sunagashi. The nie lies as finely and evenly across the blade's surface as a light dusting of snow — a hallmark of Sadamune's restrained yet powerful style.

The sword was transmitted through the Owari Tokugawa family, counted among the many named blades held by that branch of the Tokugawa clan. Though unsigned due to later shortening, it has been authenticated as a genuine work of Sadamune, and its steel and hamon suggest it dates from his mature later period.

Designated an Important Cultural Property, the blade passed down through the Owari Tokugawa family and is now held by the Token World Foundation (Toukenko Corporation).