I've done several sand points, driving them with, basically, a fence post driver. These were all in sand, along the shore of an island, where the water level was high enough. There were two layers of clay to pierce which helped to ensure adequate water quality by excluding surface water penetration. Each of these ran clear after a couple hours of pumping. They resulted in potable water with some tannins which would stain whites to tan over time.
One other well was on high ground, blasted into sandstone with dynamite until a vein of water was found. The water was a bit on the hard side. That was back in the day when it could be purchased at the local hardware store.