How should I care for the copper or alloy flower tsuba long-term?
Updated Mar 2026
Copper alloy tsuba develop a natural patina over time - a gradual darkening of raised surfaces and a slight greenish tinge in recessed areas - which many collectors consider a desirable sign of age. If you prefer to preserve the original finish, handle the tsuba with cotton gloves, as skin oils accelerate tarnishing. Occasional light buffing with a dry microfiber cloth removes surface dust without stripping patina. For deeper cleaning, a jeweler's polishing cloth works well on copper alloy without scratching the relief detail. Avoid liquid metal polishes on assembled pieces, as they can wick into the habaki (blade collar) and contact the carbon steel blade, introducing moisture. Store the complete katana horizontally in a low-humidity environment - between 40-55% relative humidity is ideal - and apply choji oil to the blade at least twice a year to prevent oxidation near the tsuba junction.