All copper-based alloys have a tendency to tarnish with age. Tarnishing is caused by oxidation from exposure to air. In order to keep them in good condition, it’s necessary to clean off tarnish and polish your objects as needed. Many customers choose to lacquer their brass/bronze products to prevent tarnishing.
Cleaning Muntz Metal / Naval Brass / Architectural Bronze
Dirt, grime, fingerprints, and slight traces of oxidation can be removed using a solution made up of 50% lacquer thinners and 50% water. Be sure to clean the panels only with the direction of the grain, never against the grain. You will need to use a lint-free cloth for the cleaning, then rinse the panel using clean water, and wipe with a dry lint-free cloth to dry.