Yonaguni (与那国) is Japan’s westernmost island — a place of famously clear, deep waters and the half-mythic underwater monument off its shore. This collector’s katana is themed around that sea: a light-blue scabbard for the island’s water and a mirror-bright blade for its surface.
Forging & Steel
The Yonaguni is built on cross-folded T10 tool steel — the stock folded across multiple axes to refine and homogenize the grain. Differential hardening lays a genuine cross hamon along the edge, and the blade is finished to a full mirror polish that makes the temper line read like light on water. The result is an abrasion-resistant blade with a durable, keen edge — true to T10’s reputation for toughness. Cross-folding works the bar along more than one axis, which tightens the grain and is why the cross hamon reads the way it does under the mirror polish. Keep the bare steel oiled and the saya dry and that bright finish holds; the balance favours a quick, controlled draw.
Fittings & Mounts
A finely carved copper tsuba with gilding sets the tone. The saya is light-blue lacquered magnolia wood evoking the island’s water, and the solid-wood tsuka is wrapped in white ray-skin shagreen for a clean, secure grip.
Specifications
| Blade steel | T10 cross-folded steel with hamon, mirror-polished |
|---|---|
| Tsuba | Finely carved copper with gilding |
| Saya | Light-blue lacquered magnolia wood |
| Tsuka | Solid wood, white ray-skin shagreen leather |
Dimensions
| Total length | 103 cm |
|---|---|
| Blade length | 71 cm |
| Handle length | 26 cm |
| Blade width | 3.2 cm |
| Blade thickness | 0.75 cm |
Is it battle-ready?
Yes. The cross-folded, differentially hardened T10 blade is sharpened and full-tang — a capable cutter as well as a striking display piece. The light-blue magnolia saya and gilded copper guard tie the whole mount back to the island theme, making it a piece that displays as well as it cuts. Compare it with the folded T10 Katana Ōkami and the reddish-bladed Katana Chikara in the full katana collection.


















