JET, Oklahoma - Grab your shovels as we visit an spot in Oklahoma where you can dig for crystals. And the kind you uncover, can't be found anywhere else in the world.

When you arrive at the Great Salt Plains in Jet, Oklahoma, it looks like the beach.

"The ground water table is so high that it brings the salt to the surface and when the water evaporates it leaves a crust of salt on the surface," said Glen Hensley, a wildlife biologist.

However, it's what's right below the surface that has people coming to this spot in northwestern Oklahoma in Alfalfa County, including my family. The Salt Plains National Wildlife Refuge happens to be the only place on earth known to have crystals with a unique hourglass image in the middle...

"It's growing, it's engulfing particles of sand, and that's what makes the hourglass formation," said Hensley.

"The tried and true method is to dig a hole a couple of feet in diameter and maybe a foot deep until the water starts to percolate up through the bottom," said Shane Kasson, the refuge manager. "You can take that water with a cup or your hand and splash it along the side of the hole and use that to wash the sand and sediment away from them."

We weren't the only ones on a mission.

"I thought it was going to be hard and it was because I dug a three-foot hole and we found a piece of petrified wood and that's it," said Sonya Norman, who was visiting from Edmond. "It's actually easier because they're all on the surface."

Norman drove about two hours to get here from Edmond and was happy she packed an extra change of clothes for her son.

"It's not a guarantee, but it's pretty close to a guarantee," said Kasson. "If you look, you'll find them."

While even the bigger ones aren't worth anything, it's the thrill of the find that brought Cory Spieker and his group here.

"Don't take the recommendations online, they had us digging too deep," said Cory Spieker, visitor from El City. "What we found was in the first two inches."

"I thought I was going to come out here and find a big, my expectations were big, but I like what we found, I really do like it," said Cassidy Spieker, visitor from Elk City.

While the kids thought we got a record breaker, our crystals were average. However, we got all of these in just a few hours, and keep in mind, not all the time was spent digging. The kids loved playing in the sandy dirt and getting dirty.

"It's a great family friendly activity," said Kasson. "It's free and you get to take home crystals."

We also had a change of clothes. The dig area is open April 1 through October 15, sunrise to sunset. The park says the salt flats heal themselves over time and after two to three years, they're back to the way they were before, that's why the dig site areas are rotated every couple of months.