I have Sonoma crackle tile. I love it. It's beautiful and not too expensive. The crackle is fine-grained and subtle, giving life to the tile, without hitting you with pattern.
I don't think the edges were sealed by the tilers before setting. I told them to, and they said they would, but they came out of the box looking like nobody had touched them before. My tiles are cream-colored with a mid-light gray grout. There has been ZERO migration of the grout into any of the crackles. None at all.
A couple of months ago I was experimenting with an extra tile. It looks to me like the glaze covers the edges of the tiles, so that's probably enough protection.
I sealed my grout after it was cured. I'm not the typical messy cook with sauces flying all over the backsplash, but I do splash occasionally. Everything cleans up perfectly.
I do have one caveat with this tile. It has a handmade look, with a tendency to lippage if your tile person isn't paying attention. It happened to me. It's in the tile, but they could have done a better job avoiding it. It looks fine until I turn on my under-cab lights, which are way in the back so easier to cast shadows.
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Concerned about dark soapstone full height backsplash
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