It depends on how large the surface is going to be. The typical slab is about 114″ x 72″; any larger and it will be very difficult to cut and transport without damaging or breaking it. If the area to be covered is larger than that, you will have seams. The two slabs are set using a seam setter that brings them as close as possible to each other and levels them. The seams are thus usually nearly invisible, but visibility will still depend on the color and pattern of the slab. All seams are filled with epoxy to maintain non-porosity.