How do I verify a purple carbon katana is genuinely high-carbon steel and not stainless?
Updated Feb 2026
Verifying that a purple carbon katana is genuine high-carbon steel rather than stainless steel is straightforward using a few reliable indicators. Full-tang construction with a visible mekugi retention pin is the first indicator - a properly constructed high-carbon steel katana will have a mekugi pin visible through the handle body, confirming the blade steel runs through the complete handle. Product descriptions should explicitly state the steel grade as 1045, T10, Manganese Steel, Damascus Steel, or another named high-carbon grade rather than 'stainless steel' or '440 stainless' - these are high-chromium content grades that cannot be properly hardened. A T10 purple carbon katana with clay tempering may show a visible hamon under directed lighting, which is impossible to produce in stainless steel and confirms differential heat treatment was performed. High-carbon steel will develop surface oxidation if not oiled regularly, while stainless steel will not rust - if the blade requires oil maintenance to prevent rust, it is almost certainly high-carbon rather than stainless. All purple carbon katana in this collection use the named high-carbon steel grades with full-tang construction.