Concrete contractor I dealt with, when he needed to do an exposed aggregate slab, he used Pepsi and water. I had the extra rocky mix which he would lay and finish just like normal. When the concrete got to the point when you wouldn't leave tracks when you walked on it he sprayed the slab with his Pepsi and water solution. Next day just wash the fines off the top of the slab with a water hose leaving the rock exposed :realcrazy: The sugar retards the set of the concrete on the surface.