Plaster Sand is simply fine (small Grained) sand. Particle Size should range between 150 to 600 microns. Government has given a specification for plaster sand as per IS 1542:1992.
Sand is manufactured from “Grit” ( below 6mm Particles), which is by product of stone
crusher. While crushing, the size below 6 mm is manufactured, which is sieved and
serrated from the metal. It is not used much in the construction industries. The
consumption of the 'grit' is very less compared to the production. Hence it is available at
very cheap rate. The sand plant is specially designed for manufacturing sand from the grit. It is a better utilization of the material. See Profitability Report