Atsu Katana (Damascus Steel & Genuine Hamon) - 竜巻

Hand-forged Atsu Katana (厚 — "Devoted Pressure") in clay-tempered Damascus steel with genuine hamon and bo-hi groove. Fully hand-polished, hand-shaped kissaki. Full tang, sharpened. Damascus steel tsuba with silver rim, Damascus steel fuchi and menuki, copper habaki, navy leather ito over genuine rayskin, shell-style saya with engraved dragon and abalone inlay, navy sageo, bamboo mekugi. Includes horn-style bronze display stand. The only katana in our catalog where even the tsuba is Damascus — the forging pattern runs from guard through blade.

Atsu Katana Specifications

Clay-Tempered Damascus with Bo-Hi

Three advanced features on one blade. The Damascus steel is folded and forge-welded from multiple layers, the genuine hamon is produced through traditional clay tempering (tsuchioki — clay on spine, exposed edge, water quench), and a bo-hi (樋 — fuller groove) runs the blade's length, reducing weight while producing the distinctive whistling sound during cuts. Bo-hi is the first new blade feature introduced since the Ginkai's horimono — and unlike decorative engravings, bo-hi serves a functional purpose: it lightens the blade by approximately 10% while maintaining structural rigidity. The forging process on the Atsu katana handles all three — Damascus folding, clay tempering, and groove cutting — in sequence.

Damascus Steel Tsuba — Matching Guard

The tsuba is forged from the same Damascus steel as the blade — the folded grain pattern visible across the guard's face, framed by a silver rim. This is unique in our catalog. Every other tsuba uses iron, copper, brass, or silver — the Atsu is the only blade where the guard is Damascus. The visible grain on the tsuba matches the blade's pattern, creating material continuity from guard through blade. The Damascus fuchi (handle collar) and menuki (grip ornaments) extend that continuity onto the handle. The Atsu does not mix metals for visual variety — it commits to Damascus across every forged component.

Shell Saya with Engraved Dragon

The saya uses a shell-style finish — dark lacquer embedded with abalone fragments that catch light in shifting iridescent colors. An engraved dragon wraps the scabbard body in relief. The combination of shell inlay and dragon engraving on one saya puts the Atsu katana alongside the Ginkai in scabbard complexity. The navy sageo and leather ito tie the saya's dark palette to the handle, keeping the entire sword in a navy-silver-black register.

Leather Ito & Genuine Rayskin

Navy leather ito wraps over genuine white rayskin (samegawa). Leather grips firmer and warmer than cotton or silk, and ages into a burnished surface through handling. The white rayskin diamonds flash through the dark leather crossings. Damascus menuki sit beneath the wrapping as grip accents — small pieces of folded steel matching blade and tsuba. Bamboo mekugi pin the full-tang blade through the solid wood handle. The Atsu joins the Kuroki and Kill Bill as the only blades in our catalog using leather ito — each with a different leather type and color.

Atsu — Forge Pressure

Atsu (厚) means "pressure" or "devotion" — the force that transforms raw steel into a finished blade. Every element of the Atsu katana references that transformation: Damascus layers beaten together under hammering force, clay tempering subjecting steel to thermal shock, bo-hi groove carved into hardened steel, dragon engraved into the saya. Nothing on this blade was easy to make. The Damascus tsuba alone required forging a separate piece of pattern-welded steel specifically for the guard — a step most smiths skip because it doubles the metalwork.

Display

Ships with a horn-style bronze stand on a dark base. The Atsu sits alongside the Ginkai, Ryujin, Kumo, and Shirokuro in our premium tier. Display where the Damascus grain on the tsuba can be examined — it is the single feature that makes this blade unlike anything else in the catalog. Pair with the Kuroki (magnolia saya, Damascus blade) to show two different philosophies of Damascus craftsmanship: raw natural materials versus shell-inlay luxury.

Frequently Asked Questions

What is bo-hi?

Bo-hi (樋) is a fuller groove cut along the blade's length. It reduces the blade's weight by approximately 10% while maintaining rigidity, and produces a distinctive whistling sound (tachikaze) during cuts. It is both a functional and aesthetic feature found on many traditional Japanese swords.

Is the tsuba really Damascus steel?

Yes. The tsuba is forged from pattern-welded Damascus steel with the folded grain visible across its face. The fuchi and menuki are also Damascus. This is the only katana in our catalog where the guard matches the blade's steel.

Is this Atsu katana sharp?

Yes. The clay-tempered Damascus blade is hand-sharpened and functional. Handle with care, store in the saya, and check local regulations before ordering.

What does Atsu mean?

Atsu (厚) means "pressure," "thickness," or "devotion" in Japanese. The name references the forge pressure that transforms raw steel into a finished blade — the heat, hammering, and folding that create Damascus patterns and refine the steel's structure.

Is the rayskin genuine?

Yes. This katana uses genuine white rayskin (samegawa) beneath the navy leather ito wrapping.