Samurai Swords (more properly called “Katana” or Long Sword) are traditionally made by the master swordsmiths from the iron produced in one smelting of iron ore each year.
The smelting is treated as a religious experience. A furnace is constructed and charcoal is lit to bring it up to the required temperature. When the temperature is right, this being judged by eye from the colour of the furnace, the iron ore is added.
After 3 days, give or take a few hours, during which the furnace keepers rest in shifts and the furnace is constantly attended, the bottom of the furnace is opened and the rough lumps of iron are raked out. All this is accompanied by various Buddhist rituals, ancient traditions and perhaps a small element of superstition.
The rough lumps are pounded (amalgamated) into one large piece. From this piece are cut the entire year’s supply of the iron, soon to become steel, for each swordmaster.
These pieces are taken away with great reverence by the swordmasters and guarded jealously as precious items.
From his block the swordsmith will then cut a piece large enough to make one Katana. Again this is done by eye. No measuring or weighing is necessary for these master craftsmen. It is often said that the master can “see” the blade he will make in the block he cuts even before the labour had begun.
The small block is heated in a furnace to the required temperature, again by eye, which is judged purely on the colour of the metal in the flames, and beaten out until flat. The flattened piece is then folded. Heated, beaten and folded again, and again, and again.
The constant heating, beating and folding has more than one purpose. First it serves to spread the carbon content of the steel evenly across the piece thus producing a steel of one grade. Secondly the steel ends up as almost microscopically thin layers within what will become the blade of the Katana.
The folded steel is then lengthened into the rough shape of a sword, constantly heated and re-heated, beaten and re-beaten until the shape, but not the curve of the classic Katana becomes evident.
The blade is then coated, in places thickly and in others thinly, with clay and heated a final time. The clay covered blade is then quenched a final time. These days this is done in water, but there are stories of old masters from past centuries quenching the blades in chicken or animal blood. Even stories that they used water mixed with their own blood.
The thickness of the clay determines the speed of cooling of the areas of the blade and it is at this stage that the cooling process actually pulls the blade into the classic curved shape of the Katana.
The clay also results in the edge of the blade, a Katana is a single edged sword, being imbued with its amazing hardness while the back of the blade is softer and more flexible. This creates a blade which will take and hold a lethal edge, but, supported by the softer and more flexible back, not one that is so rigid it will shatter on impact.
The next stage is polishing. This can take weeks and it is during this process that the layered construction of the blade and the uneven final quenching can be seen in the pattern, or signature, of the blade which slowly, so very slowly, becomes evident and one can now begin to see that beautiful pattern emerge under the careful hands of the polisher.
The blade is then fitted with a handle and guard to produce a sword. The best handles are covered in shark skin. This is used as shark skin is rough and gives a good grip. It has the additional advantage that, unlike leather bindings used in most western sword handles, it will not become slippery when soaked in sweat during battle.
This then is the finished sword, but not just any sword. This is a Katana.