TileProf says: |
Hi Lee,
Thanks for the e-mail, have only heard of this happening on French Hand made Tiles,which had a crackled glazing to them, this should have been sealed first with possibly a Grout sealer, we have one called Grout seal and Go, once the stains get into the glaze though, its almost always impossible to get it out again.
Regards Russell at Tile Doctor
http://www.tiledoctor.co.uk/GroutSealer.html |