Crystal-digging season is underway at the Salt Plains National Wildlife Refuge in northern Oklahoma.Get the latest news stories of interest by clicking here.The wildlife refuge in northern Oklahoma is open for the crystal-digging season every year from April 1 to Oct. 15. People are welcome to dig up and collect the state crystal of Oklahoma for free on the 11,200-acre salt flats. Crystal digging is only allowed from sunrise to sunset in the dig area.Get the latest news stories of interest by clicking here.To get there, guests will need to drive to the selenite crystal-digging area at 66003 Garvin Road in Cherokee. Then, once inside the gate, drive about a mile, follow the road and park in front of the orange "Dig Area" signs.Visitors are allowed to collect up to 10 pounds and one large cluster for their personal use. Selling crystals is not allowed. Officials said selenite crystals can be found right below the surface. They urge people to bring a shovel to dig a hole that is at most 2 feet deep and to pour water on the edges and bottom of the hole to find them.>> Download the KOCO 5 AppDiggers are told to put on plenty of sunscreen and to drink lots of water because it can be very hot. A restroom is located inside the gate to the left.Pets are allowed in the crystal-digging area, but they must be on a leash. Drones are not allowed. Click here for more information about Salt Plains National Wildlife Refuge.