I am working on a Black Water Dragon floor. The flagstones are aproximately 1.5 meters by 1 meter. I made each flagstone as a seperate part so if any cracks form later they will not run through the floor as a continuous crack. I also used a medium mesh to give the flagstone floor strength. The extra work takes a bit more time, but it will be walked on a lot and I want it to act as individual flagstones. I will point between the flagstone with cement grout after painting.