I rarely see cracked tiles. We use a flexible grout designed for this type of environment and the floors float anyway. We use Snap-Stone...which is a tile, basically glued into a plastic tray. The plastic trays snap together. Makes replacing a tile loads of fun...grout has to come out of course, but then you need to cut the tabs off the plastic tray to get it out.
Almost looks like an impact with that chip taken out. Or maybe it was a high edge and pressure on the tile let it sink right there. Where is that tile on the floor?
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