Changing tile colour

[Lorenzo]

We have an old fireplace with an open fire. The surround and hearth are tiled in these types of tiles (the lighter coloured ones) -

We want to update it a little, but not rip it out. I was wondering about colouring some of our tiles darker (like in the picture) just to give it a less solid and boring look.

Any suggestions about whether these type of tiles can be stained/coloured in some way. I know that there is tile paint on the market, but presumably that would remove the "mottled" effect entirely. I also have to make sure they are suitable for a fireplace too.

Many thanks in advance for any suggestions.

[Codswallop]

All I can suggest for something that is semi-transparent, so that the tile colours will not be completely hidden, is polyurethane wood stain. This is available in various shades of timber-coloured brown (oak, mahogany, teak etcetera). However, if you intend lighting the fire I doubt that any type of paint will be heat resistant. That shouldn't be a problem if you only paint tiles that are not too near the heat source.

[Mel]