How should I store and maintain a blue blade katana on display?
Updated Mar 2026
Blue oxidation finishes are more sensitive to fingerprint oils and ambient humidity than a standard polished blade. When handling for display positioning, use clean cotton gloves to avoid transferring skin oils, which can cause uneven staining over time. Apply a very light coat of choji oil or high-purity mineral oil to the blade surface every one to three months, depending on your local humidity level. Store the sword horizontally or on a tilted display stand with the edge facing upward — the traditional orientation — and keep it away from direct sunlight, which can shift the blue tone over extended periods. In humid climates, a small silica gel pack placed near the storage area helps prevent rust formation on the high-carbon steel.