The only place on Earth you can dig hourglass selenite. On a wildlife refuge in northwest Oklahoma, on the flat white bed of an ancient sea, you dig a hole in the wet salt sand, let it fill with water, and lift out clear gypsum crystals with a brown hourglass of trapped sand inside, a shape found nowhere else in the world. It is FREE and PUBLIC in a designated digging area (open a set season, roughly Apr-Oct); bring water and shade, there is no cover out on the flat.
Hourglass selenite
Other places on the map within a couple of hours.
