Help With Getting Grout off and What Products to use Advice and information on tiling and fixing tiles to a variety of surfaces

[twedspeed]

Hi is there a product that will help me get dried grout off some matte tiles - the tiles are NOT nice shiney wipe clean ceramic - they are matte tiles that have a gritty finish - Im rubbing like mad and its taken 1 day to clean ONE tile off ! - I was going to use a wire brush but Im worried Ill damage the finish - Is there a wonder product that will disolve it ???? Please note Im trying to get it off the tile face NOT from in the gaps