This staircase developed by Webb Yates Engineers and The Stonemasonry Company is unusually audacious. Developed for a residential design by RAL Architects in Formby, UK, each step of the two-story, 4.6-meter diameter helical staircase is composed of an individual block of stone, giving an impression of weightlessness as the structure circles its way up through the building's atrium towards the glazed roof above.  Read on to find out how Webb Yates achieved this feat of engineering.