I have noticed that the hard rubber at the grip section and turn knob of my pelikan 1931 LE was discoloured. This was due to perhaps exposure to the lights. I have placed the pen in the my display cabinet with lights on (when required).
The rubber parts are not anymore shining and parts of the grip section will change to brownish colour when used.
Is there anyway for the pen to return to its original black colour or to make it shine back?
Thanks for the help.