The concrete step was heavier than I initially thought to lug up the first flight of stairs, and far more difficult to release from the mold than I planned.  It all turned into a bit of a disaster really. while I was trying got free the step from it's mold , I had a fight with my boyfriend. Then the step broke into three. and the camera memory card became full just before I'd finished.  But the step fitted perfectly! the mold was all the right proportions. I went back to load the photos to free the camera and to come back to finish taking photos of the step, but when I came back the mold was gone! pretty funny ending to a pretty bad day....