The Katana is the traditional sword of Japan. The curved blade makes it effective for both the slashing moves of mounted combat and the thrusting motions of on foot battle. In the samurai culture of Feudal Japan, the Katana was a prized weapon for both its strength and beauty. The beauty was important because a well-made sword could be passed down through generations without ever showing any wear. Swordsmiths must pay special attention to the details that make a katana beautiful and durable. This is why a swordsmith might spend years perfecting his craft.
The sword begins as a block of red-hot steel, which the smith elongates by repeatedly striking it with a hammer called a Tsuchi. The process is repeated several times until the smith has the desired length of the blade. The smith then cuts and folds the blade to remove impurities and even out its carbon content. As it is being shaped, the blade takes on its signature curve.
After the sword has been shaped, it is heated again and cooled in a furnace called a clay tatara. The swordsmith uses a clay slurry to apply a thicker coat of the slurry on the spine and the body of the blade, while applying a thinner coating along the edge. This is known as differential tempering, which creates a combination of hard, sharp edges and a softer, more resilient spine. It also produces the distinctive appearance of the Hamon, a wavelike pattern present on the surface of the sword that indicates its quality. find out more information