re-silvering brass clock dial

I have been trying to re-silver the chapter ring on a longcase clock but I am a little disappoined with the results. I have been using a kit containing a silver salt of some sort plus cream of tartar. I have tried several times to obtain a finish with a reasonable sheen but I only get a dull silver/grey finish. I have tried polishing the brass to a high shine first and also tried graining the brass with an abrasive before applying the chemical. The results are the same, a dull finish. I realise the finish should not be a mirror shine but I believe there should be a sheen on the silver which I cant obtain.

Any suggestions appreciated.