Reading Jihada — Each Smith's Character in the Steel Grain

Jihada refers to the texture and forging grain visible on a sword's surface. Along with hamon, it is one of the most important aspects of sword appreciation.

Itame-hada (wood grain): An irregular pattern resembling wood grain. The most common type, found across many traditions.

Mokume-hada (burl grain): Round, knot-like patterns. A variation of itame, commonly seen in Bizen-den.

Masame-hada (straight grain): Straight, parallel lines. Characteristic of Yamato-den, conveying a clean, austere impression.

Ko-itame-hada (fine grain): Extremely fine itame. Indicates precise forging, as typified by Hizen Tadayoshi.

Ayasugi-hada (cedar grain): A distinctive pattern of continuous V-shapes. Virtually exclusive to the Gassan school.

Nashiji-hada (pear-skin): An ultra-fine texture resembling the flesh of a Japanese pear. The supreme jihada, typified by Awataguchi Yoshimitsu.

To appreciate jihada, tilt the sword under fluorescent light and observe the grain patterns revealed by the reflection. Fine jihada is described as "tsunde-iru" (closely packed), a mark of forging density and beauty.