Unsigned katana sword by Norifusa

The original signature of this katana was lost to the reforging process when its tang was shortened and thinned. However, the outstanding workmanship of this sword has helped experts identify its maker as Norifusa, a prominent swordsmith of the Ichimonji school. It has a medium-length tip almost stout enough to be classified as a “boar-neck” ridge. The steel blade features both burled and wooden grains, the latter of which appear coarse, with short and bright lines breaking up the grain. Relatively large carbide traces are scattered among finer carbides that appear near the border of the blade temper pattern, from which sharp protrusions extend, slanted toward the sword’s tip.

The temper pattern is formed by clusters of multiple clove-shaped waves occupying most of the area between the blade’s edge and its ridge. The temper pattern on the tip carries on the irregular pattern of the blade’s body, and tapers to a rounded point as it bends toward the sword’s back. A long, singular groove extending all the way to the hilt of the sword has been carved into its ridge, leaving only a thin part of the ridge near its back untouched. This sword comes with a double-layered collar of high-quality golden openwork featuring a meticulously carved triple hollyhock crest, tying it to the shogunal Tokugawa family.

— Museum description: Kyushu National Museum (CC BY 4.0), via ColBase / Japan Search.