Millions of years ago, a sea near Oklahoma used to repeatedly flood. This led to the formation of crystals as the soil used to mix with the salty groundwater. This led to the creation of the Great Salt Plains in Alfalfa County. The crystals formed are officially state crystals of Oklahoma.

As iron oxide is present in the soil along with clay particles, the crystals appear brown in shade. Since it is an amalgamation of soil and water, an hourglass shape takes place. These can be seven inches long and might weigh approx 38 pounds.

The site has attracted rock enthusiasts from several countries. They have successfully found clear and gypsum crystals across various shapes and sizes like large, intact, selenite crystals with a sand/clay hourglass present within them. The area was closed for several years to clear the World War II training artefacts but it is now opened to the public again.

For crystal digging, a separate digging area is provided. It is known as the Selenite Crystal Digging Area. The area is open to the public from April 1 to October 15. Tourists are permitted to dig from sunrise to sunset. Only in the assigned areas can tourists dig and collect selenite crystals on the salt flats. Travellers are allowed to collect only up to 10 pounds for personal use alone. It is illegal to sell these crystals.

As part of the Great Salt Plains National Wildlife Refuge, the Great Salt Plains is home to several wonders of the world. For instance, the refuge headquarters will give you an insight into the historical context of the area. Followed by Eagle Roost Nature Trail which is a gorgeous wooded wetland. You can also check out Harold F. Miller Auto Tour Route which will take you through a portion of the refuge.