[header] How to clean brass hinges [title] Determine if you have brass-plated metal. [step] There are two kinds of brass hinges: solid brass hinges, and hinges made of brass-plated steel, zinc, or cast iron. Place a magnet next to the brass hinge you're interested in cleaning. 
If it sticks, you'll know it is not made of solid brass. [substeps] If the brass hinge you're interested in cleaning is made of brass-plated zinc, cast iron, or steel, clean it very gently or the brass coating might come off.