Abstract: An exposed aggregate surface is applied to a reinforced concrete swimming pool or similar structure by pumping through a discharge nozzle a mix which is deposited as a relatively thin layer which is then worked by trowelling to compact the aggregate and draw portland cement in the mix to the surface of the coating and a fine water spray is used to wash away the excess cement. The mix comprises fine aggregate substantially smaller in size than aggregate which will pass through a 1/2 inch mesh, a rich cement to aggregate ratio for example 1:1 by volume, the aggregate being substantially free of fines and a quantity of water such that a small slump is provided.