Slate tiles 1X1

[LUCKYEAF]

Thanks in advance for any insight you can give on my problem.

We're just finishing a kitchen remodel and installed what I thought was going to be a beautiful Rustic Yellow 1x1 slate tile on the wall behind the stove and sink. There are no cabinets on the wall only a range hood above the stove. The original colors, prior to installation, were mostly pale yellows and medium grays with some blacks. After installation, the colors became more intense looking with oranges, browns, tans and black. It looks like the tile is darker, similar to what would happen with color enhancing sealers.

The installation followed all manufacturer's instructions - hardi backerboard, polymer modified thinset mortar and a polymer modified gray sanded grout. We sealed the tile prior to grouting with a natural look (no shine) penetrating sealer. After grouting we dry scrubbed the haze and followed up a day later with water and scrub pads to remove the last of the haze.

Does anyone have any ideas as to why the slate changed color on us?

[Jason_Butler]

Did you use gray mortar or white mortar to set the tiles?

Jason

[John Bridge]

Welcome Lucky. Give us a first name, please.

No idea unless it's the sealer you used --- or you haven't waited for the stone and grout to completely dry out. I'm going to move this to another forum where we can get some expert help. You'll find it with no problem.

Dear Lucky:
Obviously your slate is extremely porous.
Jason's concern is right on the money. If you used gray thin-set then the change of color could turn out to be be permanent. If you used white, then it may fade eventually. The application of an impregnator sealer before the installation is not helping, either, since it will slow-down the curing/drying process.
Wait a few more days before panicking!
Ciao and good luck,

[LUCKYEAF]

Thanks Jason and Maurizio.

We used white mortar to install the tiles and we will wait a bit longer to see if it lightens up. It might be my imagination, but I think it is a little lighter today.

Other questions about slate. Do the colors really look different under different lighting? Someone suggested that was the case.
Also, could we unintentionally have polished the slate when we were removing the haze?

Great site. Very helpful. Wish I would have known about this before we even started looking for tiles.

Eileen

[kemguru]

Hi Eileen

Sure, you could have buffed a little sheen into the surface. Probably more so on the seal than the slate itself. What’s the name of that there sealer?

As far as the darker color…just give it time. You pre-sealed, so it will take longer for the moisture to find its way out. No worries, usually.

Doesn’t everything look different under different lighting?

[Michael Meyer]

Hi Eileen Perhaps the yellowing you saw was a thin layer of iron oxide powder which was scrubbed off during your installation. While it is the general assumption that iron oxide is the typical orange color there actually are a whole host of color combinations. Inherent minerals with an external contributer. Michael of Stonehenge