
Bronze markers are made to last a century or more, but they're also surprisingly sensitive. The dark, even patina you see on most bronze plates is a protective oxide layer — strip it off and the metal underneath is exposed to weather.
Why DIY methods backfire
Acidic cleaners (vinegar, lemon, CLR) etch the surface and leave bright pink spots that turn green within months. Wire brushes gouge the cast lettering. Brass polish creates a mirror finish that oxidises unevenly and traps moisture.
What a professional restoration looks like
We start with a soft-water rinse and a pH-neutral surfactant. Cast lettering is cleared with wooden picks and natural-bristle brushes. The plate is then re-waxed with a museum-grade microcrystalline wax that re-establishes the protective layer.



