The Ancient Japanese Infused All Creation in the Hamon

Most Japanese are familiar with the term hamon. However, the origin of its invention

　is unknown. I shall review the quenching process from the earlier passage on

Japanese sword making.

In the stage before yaki-ire, using a small hand hammer, the mune, shinogi and

kissaki are formed. Next, a clay slurry is made with charcoal dust and particles of

polishing stone and is applied to the blade. First, a thin coat of clay is applied over the

whole blade, followed by a thicker coat on the back of the blade. This controls the

cooling rate of the blade at the time of quenching, causing the cutting edge to become

very hard, whilst retaining ductile qualities in the back of the blade.

In order to create a balance in the hardness of the jigane, the ancient Japanese gained

this knowledge of applying clay before yaki-ire by experience. A thick application

retained flexibility, whereas a thin application allowed the steel to become hard.　

Therefore, by applying a thick coat to the mune and shinogi, and applying a thin coat

to the cutting edge before heating and quenching, results in the formation of the

hamon (the pattern along the cutting edge that is the dividing line between the hard

and softer steels).

When you view a blade with a hamon using an electric light, the ji (the area between

the hamon and the shinogi) appears dark, and the ha (area between the hamon and the

cutting edge) appears like a white band. The border between the ji and the ha (the

nioi-guchi) is bright and easily visible. The pattern of this borderline is the hamon.

There are many variations of hamon. In the early Kamakura period, the smiths of that

area were already creating controlled hamon. However, after the Mongol invasion this

style became popular and spread across Japan. When applying the clay, transverse

lines of clay were applied, controlling the shape of the hamon. Kamakura period

onwards the shapes vary due to swordmith schools and the individual preferences of

the samurai of the various periods.

When polished using Japanese techniques, a hamon also can appear in western swords.

However, unlike Japanese swords the steel of many of these western blades is full of

impurities. In other words, this is not actually a hamon, just the difference between

the hard and soft steels. Western swords did not have intentionally patterned hamon

induced, so it is fair to say that hamon are unique to Japanese swords.

There are five various basic hamon: Suguha (straight), notare (undulating), gunome

(semi-circular formations), ko-midare (slightly undulating) and choji (clove shaped).

All hamon are usually a variation or mix of these basic themes. The final result of the

hamon is outside the control of the swordsmith’s hand, as it is subject to the power of

nature through its baptism of fire and water. It is this essence that can be appreciated

when viewing. Later, hamon became more contrived with images of Mt Fuji,

chrysanthemums, cherry blossoms, sanbon-sugi (three cedar trees) and bamboo leaf

patterns being produced on the blade.

As I cannot illustrate the hamon patterns within this article, I recommend that you

research them in a beginners book on Japanese swords that gives a simple explanation

of the basic hamon. However, I shall give a basic description. Suguha is a hamon that

runs in a straight line. Ko-midare is similar to suguha, but the line undulates slightly

and is not absolutely straight. Notare is a undulating pattern like the gentle rolling of

the waves of the sea. Gunome are semi-circular shapes. Choji are clove shapes that

appear in the hamon. Usually referred to as choji-midare, there are several kinds of

choji.

The ancient Japanese included these patterns in the blade even though the sword was

for ‘taking human life’. Living as a human in the space between heaven and earth.

　In a sense of reverence to the natural world, they created an image of all of creation

within the hamon. In world history, the sword as an instrument of civilization has

appeared among many races. However, the application of the hamon is unique to the

Japan. This is to be expected of a civilization as unique as the Japanese nation.