You can use most commercially available products designed for cleaning brass – such as Brasso® - and with a soft polishing cloth, gently rub off any marks you see on the plates. Finish off with a rub of a clean, soft cloth.
The lacquer we use in the manufacture of our fingerplates is extremely durable – but it will not withstand a sustained attack of Brasso®! Please just use a slightly damp sponge to remove any superficial marks, and finish with a gentle rub from a dry, soft cloth. Lacquered fingerplates should look as good as new again!
One option is to consider our recently added Special Antique Effect range. These do a magnificent job (if we may say so oursleves) of looking like very old fingerplates.
Another cheaper alternative (if you are not predisposed to waiting 100 years for tarnish to take hold) is to use Liberon's 'Tourmaline Brown'. This is a chemical which "paints" (and thereby darkens) the metal and so can look aged; phone your local DIY stores for pricing and availability.
