What should I know about caring for a carbon steel katana display piece?
Updated Feb 2026
Carbon steel — including 1045, 1060, 1065, and T10 grades — is susceptible to oxidation if left unprotected. For display and storage, apply a thin, even coat of choji oil (traditional clove-based sword oil) or a food-grade mineral oil to the blade surface every two to three months, or more frequently in humid climates. When handling the blade, use clean cotton gloves or avoid touching the polished surface directly, as skin oils accelerate surface rust. Store the katana horizontally on a sword stand, or vertically in its saya with the edge facing upward in the traditional Japanese manner. Avoid sealed display cases without humidity control, as trapped moisture is a common cause of rust on stored blades. A silica gel packet placed near the storage area helps regulate moisture effectively.