Carolyn, I just grouted 500sq/ft with silver and it lightened a lot! Most of the lightness was removed with a 3:1 vinegar/water and then dawn soap and water wash. It was a combination of efflorescence, polymer leaching and excess water when cleaning up grout from the tile. We had to wait a week before doing this. Its almost impossible to grout with Mapei without the grout lightening at least a shade, in my experience.
As far as your project, I can appreciate your particular eye and I’m in agreement w/ Chisos and Beth, I think the pewter is spot on. After you clean the haze from the grout as I explained above, it'll look awesome. Or maybe youve already done this? Good job choosing!
Please update on the outcome.
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Cleaning advice
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