Which carbon steel is best for a samurai sword with a visible hamon?
Updated Feb 2026
T10 tool steel and 1095 high-carbon steel produce the most vivid and well-defined hamon temper lines. Both have high enough carbon content to create a strong differential between the hardened edge and softer spine during clay tempering. T10 is the most popular choice overall because its tungsten content enhances the hardness differential and produces a particularly striking hamon with clear contrast. 1095 achieves the highest peak hardness at the edge, which can produce an extremely crisp and defined hamon boundary. 1060 can also produce a hamon with clay tempering, but the lower carbon content results in a softer, less defined line. 1045 rarely produces a visually compelling hamon because the carbon content is too low for strong differential hardening.