How is a traditional samurai sword made?

Photo of metalworker with Japanese Kitchen Kinfe

Of all the iconic national symbols, none is more representative of Japan’s time-forged traditions than the samurai sword.

Said to possess a warrior’s very soul, the samurai sword has been marvelled at for its flawless beauty and unrivalled engineering for over a millennium. Centuries ahead of its time, Japanese sword making was passed down from master to pupil for generations and revered as part art, part religious ritual. So how exactly were they made?

How samurai swords were made

The great swordsmiths of Japan were more alchemists than blacksmiths. Requiring a deeply intimate knowledge of chemical metallurgy, the traditional sword making process was anything but straightforward. Dozens of craftsmen would work around the clock for months on end, sometimes longer, to produce a single blade.

Step 1: Making the steel

The starting steel, tamahagane, is produced by smelting iron sand (sand containing iron ore) with charcoal in a large clay furnace known as a tatara. Once the correct temperature is reached, it’s up to the tatara masters to carefully monitor the tatara, feeding in iron sand and charcoal as needed. This step is crucial, and requires the team to be on hand for 72 hours without pause.

Step 2: Sorting the steel

After the three day smelting process is complete, the tatara masters break open the clay furnace to extract the tamahagane. From this, they break apart and separate the steel mass according to carbon content. When expertly combined, high-carbon steel and low-carbon steel will imbue the blade with a razor-sharp edge and toughness, respectively. A sword composed of just one type of steel would result in a blade that would be too brittle or dull easily.

Step 3: Purifying the steel

The best pieces of tamahagane are sent to a swordsmith, who heats, hammers, and folds the steels repeatedly—up to 16 times— in order to further combine the …continue reading