Many people with Carrara (which is similiar) have chosen Custom Platinum. It's a very light grey that tends to minimize patterns, if that is your goal. But, compare the color to your sample, as your tile may be different.

Hard to give recommendation with just the picture to go by as the tile can look so different in real life. Custom Bldg. Products-like #10 antique white, #365 canvas, or for even darker maybe #156 fawn. Laticrete-lots of nice colors: #23 antique white, #39 mushroom, #81 butter cream, #52 toasted almond, or for darker maybe #31 caramel. The best thing to do would be to go to the tile store with your samples and ask for some grout advice-maybe from the above listed color choices?? or they may recommend something entirely different. I don't have the color chart for TEC or mapei so can't offer any from those lines. Take your time-your tile is very pretty but the right grout is just as important. Grout color choice can be a PITA. All brands say that the sample sticks/pictures are just a representation and may not be the actual color you end up with. We used Laticrete for our floor and the grout was lighter than the sample picture. We used TEC for the backsplash and it was way darker than the sample stick. Go figure!! Hoping Bill V. will see your post and offer some advice.

Just an update...so I went with a whitish grout because at night it seemed dark since I have no undercabinet lights. I really like how the cabinets and molding tie in:) I am now deciding if I should put a piece of decorative crown and stop,or buy more tile and do the entire wall? It will be tricky making those cuts and not standing on the granite!!lol

Thanks for the comments. The Spectralock is actually not a commercial product. Used to be available at Lowes before they switched to Mapei - they switch every couple years, it seems. It is designed for regular tile installations, not specifically for pools or fountains. Yes, I let the sample board dry over night. It's been 3-4 days now. Still pink. Ugh. Online reviews for Mapei have not been great as far as grout color matching the samples, so I fear another issue there with having it not look like it should on the sample board. Some of the reviews have also indicated it's difficult to clean the haze off the tiles. Switching brands also doesn't help my having $39 invested in one of the Spectralock minis that's already opened. If I have to switch brands, I will, but I really would like some feedback on the Spectralock colors first to see if that can work. FWIW, I'm not concerned about mold and mildew on the backsplash. This is not like a tub or shower after all. What I am concerned with is food stains - spaghetti sauce, red cabbage, etc. This will be a relatively light grout color, and there are plenty of foods that can splatter and stain.