There’s a reason that these ancient Samauri swords are legendary.

Forging a Katana, a Japanese samurai sword, requires dedication, craft, and focus. Traditionally, it is a slow, intentional process. As with any true craft, the technique takes time to perfect and can be passed down through generations of swordmakers.

Below is an outline of some of the details of the process. It should help you appreciate what goes into this beautiful and legendary weapon and allow you to recognize the difference between a true sword and a hastily made imposter.

About katanas

Before we take a closer look at how these weapons are made, let’s get to know them a bit. Used in the middle ages, the swords have the expected handle, pommel, and sheath but the blade itself is what makes it special. It is a single-edged and curved with a tip to stem length of at least 23.5 inches. Most impressively, the swords have a wavelike effect that runs along the length of the blade. This effect, call a Hamon, is a byproduct of the authentic process used to create the weapon. Its presence means that the sword will remain both sharp and durable, so powerful that it can cut a man in two with a single blow.

Carabo Spain/Pixabay

Katanas also feature a spectacular history. They were first developed during Kubla Khan’s conquest of Japan as warriors needed a blade that was sharp enough to pierce through armor but also strong enough for battle. Ultimately the swords proved effective and helped the Japanese resist being conquered.

Crafting a katana

The process of making a katana is complex and can take days when it is done properly. An authentic process starts with an authentic furnace known as a Tatara, a type of clay blast furnace. Charcoal and iron sand are burned for three days and three nights in order to remove some of their impurities from the iron and to blend the two materials together. While the result, called a Tamahagne, is broken apart, analyzed, and otherwise separated according to quality.

Once pieces of Tamahagne are analyzed and sorted, they’re hammered into sheets and the best sheets become the blade. At this point, the most tedious part of the process begins as some of the best of these sheets are heated up, melded together and hammered out repeatedly. This flattens and straightens the steel block, removes some of the remaining impurities.

Throughout this process, further impurities are released the sword is strengthened through the creation of thousands of layers of steel, and an incredibly strong weapon is created.

Once a swordmaker determines that a katana is ready to be forged, they heat the weapon up another time, create an incision in the center, and fold the two parts of the blade upward. Then the blad is hammered until it again repeats its original dimensions. This entire process is also done repeatedly, as many as six times. This final product is then cut into three pieces, a fourth piece is added, and these are also repeatedly pounded together and two outer sides of the sword develop around an inner layer.

The process is the hallmark of a true katana

Throughout this process, the sword is strengthened through the creation of thousands of layers of steel, and a brilliant Hamon is created. In addition, the ways that the layers are folded into each other, the way the impurities are released or retained, and the way that the heating occurs will affect the blade, the sword’s strength, and its appearance. All of these factors lend themselves to the creation of a unique and impressive sword that just can’t be replicated by easier means.

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