Hi Mary. Yes you can have your tile setter add a sealer additive to the grout when they mix it or you can apply a sealer to the entire backsplash after it's installed. You can do the sealer application after installation if the backsplash is a natural stone, as the pebble is. You'll want to re-apply the sealer periodically to keep the grout and stone sealed. Pebble mosaics come in full stone sheets or as a sliced stone, which would be a little easier to wipe clean because it gives you a flat surface.
Spartan Stones
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