HAMON
Hamon
In swordsmithing, is a visual effect created on the blade by the hardening process. The hamon is the outline of the hardened zone which contains the cutting edge . Blades made in this manner are known as differentially hardened, with a harder cutting edge than spine, or "mune" . This difference in hardness results from clay being applied on the blade prior to the cooling process . Less or no clay allows the ha to cool faster, making it harder but more brittle, while more clay allows the mune to cool slower and retain its resilience.The above text is a snippet from Wikipedia: Hamon (swordsmithing)
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