The artificial sand produced by proper machines can be a better substitute to river sand. The sand must be of proper gradation (it should have particles from 150 microns to 4.75 mm in proper proportion). Natural River sand has sky rocketed and its consistent supply cannot be guaranteed. Under this circumstances use of manufactured sand becomes inevitable.
Now-a-days, Vastu Shastra is more popular, consults Vastu by many people while constructing a house. As per Vastu Shastra, the building material must be free from traces of human or animal body. The river sand contains bones of human beings and animals. The shells are also a kind of bone. It is not easy to take out all such things present in the river sand. Hence, the best solution for this is to use artificial/crushed sand of good quality for human well being.