Brass is a zinc-copper alloy. Brass can become dull as dust and oil build-up. Use magnets to determine whether the object is pure brass. If the magnet is attracted to the object, it is not pure brass or it is just plated with brass.
Brass can be seen in the hardware and pneumatic tool accessories in life. The brass material has a golden luster, so the brass accessories have a unique appearance and good corrosion resistance. And because the brass material itself is easy to machine, toolmakers can create brass fittings of all types, shapes and uses.
In life, if the brass objects are only stained with dust and oil, they should be cleaned with warm water and neutral detergent. Do not use any corrosive detergent to clean non-pure brass objects, because the coating is very thin and easily scratched. Use a soft cloth dampened with the diluted detergent to wipe all over the brass object.
Toothpaste can be used as a mild polish. Mix equal parts white vinegar and water and add a cup of flour, which also acts as a polish. Use a toothbrush dipped in the polishing compound to remove the dust in the gaps on the brass objects, and the action should be light to avoid wear.
When removing the surface varnish, place an old newspaper on the table, apply the varnish remover with a brush, and apply it to the surface varnish of the brass object. Gently rub the varnished brass with a cloth dampened with polish, then dry it with a different cloth after a few minutes. At this point the brass should regain its luster. Recoat with varnish to protect the brass and make it shine longer.