How should I care for a tamahagane katana on display?
Updated Feb 2026
Tamahagane is a high-carbon steel and will develop surface oxidation if neglected, so routine maintenance is essential. Every two to four weeks — or after any bare-hand contact with the blade — wipe the surface with a soft lint-free cloth to remove fingerprints, then apply a thin film of choji oil (clove-infused mineral oil) using a fresh cloth or traditional uchiko powder ball. Store or display the katana in a room with stable humidity, ideally between 40% and 55% relative humidity; a small silica gel pack inside the saya helps buffer moisture. Keep the blade in its saya when not actively being admired, and always handle it with clean cotton gloves. Avoid silicone-based sprays, as they can leave residues that interfere with the traditional polish. With consistent care, the jihada grain and hamon will maintain their clarity for decades.