20 Martin Place, Sydney, Visual Mock Up by G.James Glass and Aluminium Published October 29, 2013 at 1620 × 1080 in 20 Martin Place, Sydney, Visual Mock Up by G.James Glass and Aluminium ← Previous Next → This mock up is large in comparison to most. The completed prototype is 3 stories in height, about 10m wide, and is being constructed off site at a G.James facility.