nail varnish!!! tape around the medal so as not to varnish the material and coat your medals with your missus nail varnish, any colour. leave to dry for a few hours...make sure it is very dry!!! then apply another coat, this time wipe it all off with a cloth, in doing so it removes the previous layer of varnish too, hey presto, fecking shiney medals and as a bonus they seem to stay shiney for longer too!
The next time you get your medals mounted, keep them stripped after you polished them, then go to a jewellery shop and have them silver dipped, you won't have to polish them again, I believe this is what the Guards do!
i use " silvo tarnish guard " its good, then put the medals wrapped up in a air tight resealable bag , i also shine my NATOS they look better , i know your not supposed to, but they look sh-t all smokey .
Had mine dipped some years ago and they are all court mounted, and apart from my UN medals (compressed cardboard anyway) the rest look lovely, but......I did ding one of them once (Rhodesia Medal) at the back and it started to go a bit rusty (not tarnished), I think the process of getting them dipped, strips off a layer of nickel, so be aware.
Mess Dress Ltd In Bournmemouth does the job of dipping, for a cost of course..so all I do now is get a new Selvit cloth and give them a rub up...jobsagoodun