UK White rings on reclaimed quarry tiles

[Sazzle]

Hi there. Wondering if anyone can help? We had a path laid using reclaimed quarry tiles on top of a new concrete base. It looked fine to start with, but a few days after laying, some of the black tiles started to show white haze / rings. I presumed grout haze so tried white vinegar and then a cement remover from Topps Tiles. Neither shifted it. So then I googled it and wondered if it is efflorescence, however it does not brush off with a wire brush and it comes back immediately after washing with water - so maybe not? I’m not sure what else to try. The tiles were laid about three weeks ago. Any other ideas welcome. Thanks.

 

[Dave]

Hi. Where the tiles sealed prior to grouting?

 

[Sazzle]

Hi. Where the tiles sealed prior to grouting?

No, they weren't - should they have been? We weren't advised to by the tiler who laid them. It's an external path.

 

[Dave]

No, they weren't - should they have been? We weren't advised to by the tiler who laid them. It's an external path.

They are a none glazed tile and a porous body. Some dust pressed vitrified ones are ok to grout none sealed then others aren’t.
I would suggest using a colour enhancing sealer to bring out the depth of the tile. Use on a single tile first and see if the result is satisfactory

 

[Sazzle]

Hi. Where the tiles sealed prior to grouting?

They are a none glazed tile and a porous body. Some dust pressed vitrified ones are ok to grout none sealed then others aren’t.
I would suggest using a colour enhancing sealer to bring out the depth of the tile. Use on a single tile first and see if the result is satisfactory

Thanks Dave - I'll try that.