The best way to install 12 in. x 12 in. White Polished Marble tile on my dinning room Wall. Do I have to use backer board. and white thinset or dark thinset it will be 8ft tall to 6ft wide around my electric wall mount fireplace.
There is no water near this wall is accent wall in dinning room.
I would go with the white thinset just to avoid seeing any of the grey in the spaces between tile. This would be true if you are grouting or just butting the edges together.
You may even find a mastic that will work - and will be easier to install the tile. However, you'll likely have to do a few rows at a time, let the mastic cure and then continue.
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