Removing tile adhesive

[drawis]

Hi. I have put some quarry tiles down recently using grey tile adhesive/grout (the flexible stuff).

Stupidly and try as I might in a few places I have got some traces of the adhesive- no more than smears really- that have dried onto the surface of a couple of the tiles.

I don't want to get too heavy handed and start sanding and scraping the tiles for risk of damage. Is there any product available that would help me get it off. Would heat/steam? Some sort of solvent?

Thanks