The never-ending bathroom remodel may actually be approaching completion! I'm finally tiling the shower. I tiled the floor of the shower with a flat, natural stone mosaic. Now I'm doing the side walls with a 9x12 white tile, laid in a brick pattern. Because the bottom tile is stone, it doesn't give a perfectly smooth surface for the wall tile to land on. There's a small gap between the wall and floor tile (about a 1/16", depending on the height of the stone). Now I'm wondering what to fill this space with? I could squeeze grout into this joint between the wall and the floor or use a high quality silicone caulk. I'm leaning towards the caulk because it can flex a little, but I'm worried about how long it will last. If it matters, the foot of the shower is on an outside wall, the back (long side) is against an unheated attic, and the head of the shower is along a closet. Thanks for any thoughts, suggestions, ideas or experience with this.