Removing excess dried grout

[Alladin]

Hi, I'd like some advice on removing excess dried grout. My builders did not clean up very well and have left excess grout on the floor tiles. The black grout has now hardened and left a greyish film on the tiles making them look dull. I'd appreciate your advice, thanks.

 

[sWe]

I think my british collegues would recommend something called "Lithofin Cement Away" and a rough sponge.

 

[Turkish]

Lithofin cement away may work depending on the type of tile i believe.

Turkish

 

[TilingLogistics]

Depends a lot on what the tiles are made of.

Kev

 

[justlyndon]

Something a little different but I have found turps and a rough cloth works really good